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Hydrogeologic Framework of the Southwest Florida Water Management District
(FGS: Bulletin 68) is here: http://www.uflib.ufl.edu/ufdc/?b=UF00087428
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FLORIDA GEOLOGICAL SURVEY
Tamiami Formation
Lithology of the Lower- to mid Pliocene
(Missimer, 2002) Tamiami Formation
(Mansfield, 1939) is difficult to characterize due
to the large number of sediment facies it
contains. These facies occur over a large region
of southern Florida and represent a complex set
of depositional environments (Berndt et al.,
1998). The Tamiami Formation consists of a
wide range of mixed carbonate/siliciclastics
(sandy limestone, sand and clay with varying
percentages of phosphate grains) and shell beds
that are subdivided as members (e.g., Ochopee
Limestone Member) south of the study area
(Missimer, 1993). The Tamiami Formation is
unconformably overlain by the Caloosahatchee
Formation and overlies the Peace River
Formation either conformably or
unconformably.
Where present in the study area, the Tamiami
Formation is part of the IAS/ICU and SAS
(Bemdt et al., 1998). A semi-regionally
extensive clay layer within the Tamiami
Formation comprises the top of the IAS/ICU,
whereas the uppermost higher permeability
sediments are hydraulically connected with the
SAS.
Sands and finer-grained facies probably
represent deposition in a regressing Tamiami sea
in the brackish water of a lagoon or bay (DuBar,
1962). Deposition of the shell beds are most
likely the result of storms and processes
occurring in shallow coastal waters (Missimer,
2001). Phosphatic quartz sand facies containing
giant barnacles and echinoids exposed along
Alligator Creek and in pits near Acline
(Charlotte County) are thought to represent
deposition in a shallow water, nearshore
environment (DuBar, 1962).
Cypresshead Formation
The Upper Pliocene Cypresshead Formation
(Huddlestun, 1988) is composed entirely of
siliciclastics, predominantly quartz and clay
minerals (Scott, 1992b; Berndt et al., 1998). It
consists of characteristically mottled reddish
brown to reddish orange, unconsolidated to
poorly consolidated, fine to very coarse grained,
clean to clayey sands (Scott, 2001), some of
which are cross bedded. Discoid quartz pebbles
and mica are also often present. Clay beds are
generally thin and discontinuous. Overall, the
clay content varies from trace amounts to more
than 50 percent, averaging 10-20 percent (Scott,
1992b). Due to weathering, the clays are often
altered to kaolinite. Davis et al. (2001) describe
three lithozones within the unit, which are based
on color, sedimentary structures and varying
proportions of siliciclastics. Original fossil
material is not present in the sediment but poorly
preserved casts and molds of mollusks and
burrow structures are occasionally present
(Scott, 2001).
The Cypresshead Formation occurs in the
central uplands of the Florida peninsula south
into Highlands County (Arthur, 1993; Scott et
al., 2001). Exposure of the formation generally
occurs above 100 ft. (30.4 m) MSL (Scott,
1992b, 2001). In the northern half of the study
area, the unit lies unconformably on Eocene
carbonates, whereas in the southern half it
unconformably overlies Hawthorn Group
sediments. The Cypresshead Formation can be
readily distinguished from the Hawthorn Group
because the younger unit is non-phosphatic,
contains prominent horizontal bedding and cross
bedding, is largely nonfossiliferous and contains
burrow and bioturbation structures (Huddlestun,
1988). Along the Lake Wales Ridge, the SAS is
comprised of sediments from the Cypresshead
Formation and undifferentiated sediments (Scott,
1992b). Huddlestun (1988) suggests that the
depositional environment was coastal marine
(see also discussion of Figure 7 on p. 15).
Caloosahatchee Formation
The Caloosahatchee Formation was first
recognized by Heilprin (1887) as a Pliocene
formation he called the "Floridan Beds." Dall
(1887) also considered the deposits Pliocene and
described many of the fossils; he referred to
them as the Caloosahatchee Beds or Marls.
Scott (1992c) includes sediments informally
referred to as the Bermont formation within the
FLORIDA GEOLOGICAL SURVEY
Wilson, W.E., 1977, Groundwater resources of DeSoto and Hardee Counties, Florida: Florida Bureau of
Geology Report of Investigation 83, 102 p.
Wilson, W.L., and Beck, B.F., 1988, Evaluating sinkhole hazards in mantled karst terrane, in Sitar N., ed.,
Geotechnical aspects of karst terrains; New York, American Society of Civil Engineers, p. 1-24.
Wingard, G.L., Weedman, S.D., Scott, T.M., Edwards, L.E., and Green, R.C., 1994, Preliminary analysis
of integrated stratigraphic data from the South Venice corehole, Sarasota County, Florida: U.S.
Geological Survey Open-File Report, 95-3, 129 p.
Winston, G.O., 1971, Regional structure, stratigraphy and oil possibilities of the South Florida basin: Gulf
Coast Association of Geological Societies Transactions, v. 21, p. 15-29.
Winston, G.O., 1976, Florida's Ocala Uplift is not an uplift: Bulletin of the American Association of
Petroleum Geologists v. 60, p. 992-94.
Winston, G.O., 1996, The Boulder Zone dolomites of Florida, Volume 2: Paleogene zones of the
southwestern peninsula: Miami Geological Society, 64 p.
Wolansky, R.M., and Corral, M.A., Jr., 1985, Aquifer tests in west-central Florida, 1952-76: U.S.
Geological Survey Water-Resources Investigations Report 84-4044, 127 p.
Wolansky, R.M., and Garbode, J.M., 1981, Generalized thickness of the Floridan aquifer, Southwest
Florida Water Management District: U.S. Geological Survey Open-File Report 80-1288, scale
1:500,000, 1 sheet.
Wolansky, R.M., Spechler, R.K., and Buono, A., 1979a, Generalized thickness of the surficial deposits
above the confining bed overlying the Floridan aquifer, Southwest Florida Water Management
District: U.S. Geological Survey Open-File Report 79-1071, scale 1:250,000, 1 sheet.
Wolansky, R.M., Barr, G.L., and Spechler, R.M., 1979b, Configuration of the bottom of the Floridan
aquifer, Southwest Florida Water Management District: U.S. Geological Survey Open-File
Report 79-1490, scale 1:250,000, 1 sheet.
Wolansky, R.M., Barr, G.L. and Spechler, R.M., 1980, Configuration of the top of the highly permeable
dolomite zone of the Floridan aquifer, Southwest Florida Water Management District: U.S.
Geological Survey Open-File Report 80-433, scale 1:250,000, 1 sheet.
Wolansky, R.M., Haeni, F.P., and Sylvester, R.E., 1983, Continuous seismic-reflection survey defining
shallow sedimentary layers in the Charlotte Harbor and Venice areas, southwest Florida: U.S.
Geological Survey Water-Resources Investigations Report 82-57, 83 p.
Yobbi, D.K., 1996, Analysis and simulation of groundwater flow in Lake Wales Ridge and adjacent areas
of central Florida: U.S. Geological Survey Water-Resources Investigations Report 94-4254, 82 p.
BULLETIN NO. 68
APPENDIX 1. COMMENTARY ON FLORIDA HYDROSTRATIGRAPHIC
NOMENCLATURE.
Considerable debate exists with regard to hydrostratigraphic nomenclature in the study area. While it
is beyond the scope of the present study to formally rename principal aquifer systems in southwestern
Florida, especially given the pending recommendations of the CFHUD II (Copeland et al., in review),
some discussion is warranted. This is due in part to the lack of a formal hydrostratigraphic code (Seaber,
1988), unlike that available for lithostratigraphic nomenclature (North American Commission on
Stratigraphic Nomenclature, 2005). Hydrostratigraphic unit definitions and nomenclatural guidelines,
however, do exist. Poland et al. (1972) define an aquifer system as "A heterogeneous body of intercalated
permeable and poorly permeable material that functions regionally as a water-yielding hydraulic unit; it
comprises two or more permeable beds separated at least locally by aquitards that impede groundwater
movement but do not greatly affect the regional continuity of the system." Neuendorf et al. (2005) define
an aquifer system as "A heterogeneous body of intercalated permeable and less permeable material that
acts as a water-yielding hydraulic unit of regional extent." According to nomenclature guidelines set
forth by Laney and Davidson (1986), aquifer system names should not be derived from relative position.
In consideration of these definitions and guidelines, all or part of the SAS and IAS/ICU may be
considered inappropriately named. On the other hand, Macfarlane (2000) suggests that aquifer system
names should be retained if they are entrenched in the scientific literature or legally defined in a state's
regulatory framework.
With regard to naming confining units, Laney and Davidson (1986) suggest that the name could be
based on the aquifer it confines (i.e., the aquifer it overlies). Intuitively, a confining unit may also be
named after the aquifer system in which it resides, especially if that unit crosses multiple
lithostratigraphic units precluding a lithostratigraphic-based name. The MFCU, which has been adopted
by the CFHUD II accordingly follows this line of reasoning.
Any proposed changes in Florida's hydrostratigraphic nomenclature will hopefully address the
IAS/ICU, in which relative permeability is an important consideration. In the northern part of the study
area, confining to semi-confining sediments are dominant, whereas in the southern part of the study area,
distinct local to sub-regional zones of higher permeability exist. Some hydrogeologists prefer to
characterize the northern area as ICU and the southern area as IAS; however, it is noteworthy that a
system (IAS) and a unit (ICU) are not at the same hierarchical level (Aadland et al., 1995). As a result,
the ICU would be a unit of the IAS.
The concept of a confining system should also be considered for the IAS/ICU. Jorgenson et al. (1993)
define a confining system as "two or more confining units separated at most locations by one or more
aquifers that are not in the same hydraulic system." Renken (1998) clarifies this definition by stating
"...confining units that may contain local aquifers, but which function together to retard the vertical
movement of water, are called confining systems." In consideration of these definitions, and Laney and
Davidson's (1986) suggestion on nomenclature (i.e., avoid naming based on relative position), the IAS
may be more appropriately named the Upper Floridan confining system, which would allow for presence
of hydraulically disconnected permeable zones within a system that confines the FAS. In the study area,
the northern lateral equivalent of this confining system could be named the Upper Floridan confining
unit. Alternatively, the area could simply be recognized as part of the Upper Floridan confining system.
Naming these systems or units relative to the FAS may be more appropriate than using a
lithostratigraphic reference because the FAS, as well as its overlying confining/semi-confining sediments
are not limited to a single lithostratigraphic formation or group. For example, to name the IAS/ICU based
on association with the Hawthorn Group may lead to confusion given that part of this lithostratigraphic
package is included in the UFA.
FLORIDA GEOLOGICAL SURVEY
Topography
0 5 10 20 30 40
Miles
0 5 10 20 30 40
Kilometers
Scale 1:1,750,000
Projection: Custom FDEP Albers
Gulf
of
Mexico
Explanation
|J |Study Area
- Water Management Districts
Elevation
310ft
155 ft
Oft
F *
Figure 5. Shaded relief topography of the study area based on 15 m (49 ft) resolution digital
elevation model DEM (digital elevation model) (Arthur et al., in review).
V.
FLORIDA GEOLOGICAL SURVEY
inversion, is thought to have been an important
factor in the origin of the Brooksville Ridge
(White, 1970; Knapp, 1977). Karst features are
abundant along the axis of the Brooksville
Ridge. These features are generally internally
drained and locally breach the low-permeability
sediments in the subsurface and serve as focal
points of aquifer recharge. Ecosystems present
within the Brooksville Ridge area include scrub
and high pine, temperate hardwood forests (with
less extensive swamps), pine flatwoods, and dry
prairies (Crumpacker, 1992).
The Western Valley is located east of the
Brooksville Ridge and Tsala Apopka Plain and
west of the Sumter and Lake Uplands (Figure 6).
It is also bound to the north by the Northern
Highlands and the Polk Upland to the south. The
Western Valley is approximately 140 mi (225
km) long and between 5 and 15 mi (8.0 to 24.1
km) wide; elevations average approximately 40
ft (12.2 m) MSL and range up to 100 ft (30.5 m)
MSL. Ecosystems present in the Western
Valley include temperate hardwood forest (to
the north), scrub and high pine, minor swamps,
pine flatwoods and dry prairies (Crumpacker,
1992). The Western Valley is characterized by
its gently rolling limestone karst plains
containing a veneer of Pleistocene sediments
overlying Eocene carbonates (Rupert and
Arthur, 1990). The Tsala Apopka Plain is
believed to be a relict feature of a larger paleo-
lake (White, 1970). Scott (2004) proposes
reclassification of the Western Valley into the
Williston Karst Plain and Green Swamp Karst
Plain.
The Polk and Lake Uplands, located between
the Gulf Coastal Lowlands and the Lake Wales
Ridge are approximately 100 mi (161 km) in
length and range in elevation from 80 ft (24.4 m)
MSL to 130 ft (39.6 m) MSL. Pine flatwoods
and dry prairies with lesser amounts of
temperate hardwood forest, scrub and high pine
comprise the ecosystems in these uplands
(Crumpacker, 1992). A scarp with relief of
approximately 25 ft (7.6 m) separates the Polk
and Lake Uplands from the Gulf Coastal
Lowlands and Western Valley (Arthur and
Rupert, 1989). These two uplands contain three
minor ridges: the Winter Haven Ridge, the Lake
Henry Ridge and the Lakeland Ridge (White,
1970). The land surface is comprised mostly of
mild to gently rolling hills gradually increasing
in elevation eastward. Miocene-Pliocene clays in
this region overlying older carbonates create a
hydrogeologic environment conducive to the
rapid formation of large cover-collapse
sinkholes. Scott (2004) proposes to rename the
Polk Uplands in combination with the DeSoto
Plain: the Polk-DeSoto Plain. The part of the
Lake Upland in the present study area is
proposed to be renamed the Green Swamp Karst
Plain (Scott, 2004).
The DeSoto Plain is a broad, gently sloping
area south of the Polk Upland, east of the Gulf
Coastal Lowlands and west of the Lake Wales
Ridge. Elevations vary between 30 and 100 ft
(9.1 to 30.5 m) MSL (Wilson, 1977). The
DeSoto Plain varies from 10 to 40 mi (16.1 to
64.4 km) in length from north to south and 10 to
50 mi (16.1 to 80.5 km) in width from west to
east. Ecosystems present within the area include
pine flatwoods and dry prairie with minor
swamp, scrub and high pine (Crumpacker,
1992). The lithology consists of thick sandy
clays over Pliocene and Miocene limestones of
poor induration.
The most prominent geomorphic feature in
the study area is the Lake Wales Ridge. This
large elongate upland extends from Lake County
south to Highlands County, where it is flanked
by paleodune fields on the eastern margin (Scott
et al., 2001). Ecosystems on the Ridge include
freshwater marsh, pine flatwoods and dry
prairies (Crumpacker, 1992). A belt of lakes
dominate the Intraridge Valley in the southern
part of the Lake Wales Ridge. Geophysical
investigations of lakes within the Intraridge
Valley confirm a karst-related origin: irregular,
discontinuous seismic reflectors underneath
some lakes reveal breaches through confining
beds overlying the FAS (Evans et al., 1994;
Tihansky et al., 1996), thus indicating that the
large collapse features occurred prior to or
during Pliocene siliciclastic deposition (Arthur
et al., 1995).
Elevations on the Lake Wales Ridge range
from approximately 70 to 312 ft (21 to 95.1 m)
MSL, the latter forming a hilltop feature known
as Sugarloaf Mountain in Lake County. Unlike
the geology of the Brooksville Ridge, the Lake
NORTH Plate 35. Cross section: FF-FF' Polk, Highland, and Glades Counties SOUTH
FF FF
T30SI T31S T-SIT-2T -T2SIT-3S T3S I T-4 T34SIT35S T35SIT36S T36SIT37S T37SIT38S T3ASNIAT39S T39SIT4S TNI TS
500 50D
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20AMMA UDSC 0 50 cto0 4OOoo
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FEET METEAS \W-14883 W-16305 W-14884 W-6581 W- 17000 W/-15644 W/-17001W164FET EEA
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F M I L M.DOL,,DMOF HATCH PATTERNS)
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MOM c M.AM
Plate 7. Cross section: D D' Citrus and Sumter Counties
CnRUS CO. | SUMTER CO.
EAST
R20E I R21E
R21E | R22E
TSALA WfHALCOOCHEE R
APOPKA R TER
LAKE I JUNIPER
CREEK
100
300-
250 - 0
200 - 60
150-
40
100-
20
FEET METERS
0 100
300 -
ROMP 111
W-16022
HAWTHORN GROUP
UNDIFFERENTIATED
M,C
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LIMESTONE
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M.I3T.C.D .
M.D
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M.D,T.I FORMATION
M
M.I
M
M.R
EXPLANATION
HATCHING PATTERNS
LIMESTONE S
SURFICIAL
GRAVEL FINE MEDIUM COARSE
DOLOSTONEINTERMEDIATE
--DOLOSTONE^- ^_ k AQUIFER SYSTEM/
.. LCONFINING UNff
SAND FINE MEDIUM COARSE hI FLORIDAN
.--I DTFRRETNFI f LIMESTONE AND DOLOSTNEWMF-- .
MID-FLORIDAN
CONFINING UNIT
SILT
FINE MEDIUM COARSE
CLAY CHERT SHELL BED GYPSUM
SEMI-CONFINED TO UNCONFINED
FLORIDAN AQUIFER SYSTEM
I,5,L
M,CJ.Ch
SUWANNEE UDSC
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LIMESTONE .
M.D
M.D
M,DR,
AVON PARK
FORMATION
COMMENTS
M MICRITE T SILT
S SAND C CLAY
P PHOSPHATE GRAVEL Sh SHELL
p PHOSPHATE SAND D DOLOSTONE
0 ORGANIC L LIMESTONE
R SPAR H HEAVY MINERALS
I IRON STAIN NO SPL NO SAMPLE
Q QUARTZ G GYPSUM
A ANHYDRITE Py PYRITE
Ch CHERT U UMONITE
HORIZONTAL SCALE
MILES
0 50 100
I 1 0 50 100
GAMMA (CPS) I I I
GAMMA (CPS)
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0
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AVON PARK
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AVON PARK
FORMATION
0 1 2 3 4 5
0 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGGERATION IS APPROXIMATELY 7
107 TIMES HORIZONTAL SCALE
WEST
R17E R18E
ROMP 109
W-14917 ROMP 110 ROMP LP-4
W-16611 W-16311
R18E I R19E
R19E I R20E
ROMP 108 C
W-15685
- 80
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200 -_ 6o
150 -
100 -
50 -
0-
- 50-
-100 -
-150
300-
250-
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150-
100-
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0-
- 50-
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80
60
40
20
0
- 20
0
20
- 20
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FEET METERS
100
3oo
-200 -- 60
- -100
-400 -120
-450 -
--140
0 +
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-600-
- 50-
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- -160
- -180
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-200 60
-700
-750 -
-800-
-250-
-300-
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- -220
- -240
-400 -- 20
-450 -
-140
-500-
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-600-
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-700 -
-750 -
-800-
- -220
- -240
D-A., -.. -'.
1 I I I I I
------------
-------------
I
I
FLORIDA GEOLOGICAL SURVEY
Figure 11. Helicostegina gyralis, a foraminifer common within the Oldsmar Formation (bar = 1 mm).
The contact relations between the Oldsmar
and Avon Park Formations are generally subtle
and difficult to identify within the study area,
which supports the interpretation that the contact
is possibly conformable (Braunstein et al.,
1988). In general, the contact grades from a
dolostone to a chalky white limestone. In many
cases, however, these characteristics are not
present. A useful faunal indicator of the
transition into the Oldsmar Formation is the
appearance of abundant Helicostegina gyralis
(Figure 12; Miller, 1986). Although this
foraminifer does not exclusively occur in the
Oldsmar Formation, it generally appears in
lowermost Avon Park Formation and increases
in abundance in the Oldsmar Formation
carbonates.
The Ocala Limestone unconformably
overlies the Avon Park Formation throughout
nearly the entire study area; exceptions include
parts of Levy and Citrus Counties (Avon Park
Formation exposures) or where the Ocala
Limestone is absent in the subsurface
(northwestern Osceola County). The contact
between these two units is readily apparent in
many up-dip locations and difficult to determine
down dip. The more obvious contact relations
occur where: 1) lithology of the Avon Park
Formation is tan to brown dolostone, overlain by
white to cream limestone of the Ocala
Limestone (e.g., W-16456 [ROMP 49], Plates
14 and 33; W-9059, Plates 23 and 34) and 2) in
the case where both units are limestone, the
uppermost Avon Park Formation is grain-
supported and contains disseminated organic or
thin (less than 2 inches; ~ 5 cm) beds of peat (in
some cases varying toward lignite), whereas the
lowermost Ocala Limestone is finer grained and
skeletal (e.g., W-720, Plates 6 and 29; W-12943
Plates 12 and 21). Although the Avon Park
Formation is not defined based on bio-
assemblages, additional contact indicators
include the appearance of diagnostic
foraminifera and echinoids listed above, as well
as abundance of coralline algae.
Throughout most of the southwestern part of
the study area, including nearly all of Manatee
and Sarasota Counties, the contact between the
Avon Park Formation and the Ocala Limestone
is dolomitized (e.g., Plate 18) and as a result,
formation boundary delineation is difficult. In
this situation, subtle characteristics can be used
to delineate the two units. Dolomitization of the
limestones with slightly varying textures may
yield differences in dolostone textures and
dolomite grain sizes. Fossil molds are another
useful indicator, because fossil molds of
diagnostic fossils may help narrow the
uncertainty. For example, narrow, discoid vugs
may represent prior Lepidocyclina sp. whereas
smaller cone-shaped vugs may represent where
Cushmania or Fallotella sp. were present prior
FLORIDA GEOLOGICAL SURVEY
Figure 19. Statistical summary of SAS transmissivity data from Southwest Florida Water
Management District (2006b). The horizontal (x) axis of the box plots corresponds to the histogram
x-axis. Asterisks in the box plot denote statistical outliers.
Figure 20. Statistical summary of SAS specific
Management District (2006b).
yield data from Southwest Florida Water
Summary for SAS T (ft^2/day)
0 1500 3000 4500 6000 7500
95% Confidence Intervals
Mean- I I
Median- I I
500 1000 1500 2000 2500 3000
Anderson-Darling Normality Test
A-Squared 1.50
P-Value < 0.005
Mean 1830.4
StDev 2119.8
Variance 4493649.8
Skewness 1.80288
Kurtosis 2.50311
N 15
Minimum 20.0
1st Quartile 374.0
Median 1260.0
3rd Quartile 2206.0
M axim um 6930.0
95% Confidence Interval for Mean
656.5 3004.3
95% Confidence Interval for Median
459.2 2041.3
95% Confidence Interval for StDev
1552.0 3343.2
Summary for SY
0.00 0.05 0.10 0.15 0.20 0.25
95% Confidence Intervals
Mean- I
Median- | -|
0.050 0.075 0.100 0.125 0.150 0.175 0.200
Anderson-Darling Normality Test
A-Squared 0.74
P-Value 0.036
Mean 0.14617
StDev 0.09114
Variance 0.00831
Skew ness -0.59933
Kurtosis -1.35168
N 10
M inim um 0.00510
1st Q uartile 0.05625
Median 0.20000
3rd Q uartile 0.20500
M axim um 0.25660
95% C confidence Interval for Mean
0.08097 0.21137
95% C confidence Interval for Median
0.05117 0.20685
95% Confidence Interval for StDev
0.06269 0.16639
WEST
M
150 -- 40
o100 - 30
O0
50 -
10
0 0
- 10
- 50 to
150
40
100 20
50
0 0
- 50
-20
- 100
40
- 150
-B60
-250
-60
-300
- 100
-350
--020
-400 _'M
-450
-140
-50 -
-160
-550
--160
-650 -2W
- 7600
-700-_
--220
-750
-240
- 800-
-050 -- -26
-900
-950
-300
-1000 -
-1050 - -320
-1100 -
-340
-1150 -
-380
-1200
- -- -400
Plate 16: Cross section: M-M' Manatee County
RISE R19E RISE R20E R20E R21E
ii ii
S1
R21E I R22E
SCHROEDER ROMP 33 ROMP 32
W-50098 W-16784 V-16257
0 375 750
0 50 1o 150o I 100 200 GAMMA (CPS)
GAMMAcCPS)> GAM M CPS)> UDSC c Cs",S
GAMA (CPS) C UDSC S
9b .. .
EAST
T35S T34S M
1x
T.D. 1713' BLS
TR 7-2
V-17057
R17E RISE
TR 7-1
V-15166
TR 7-4
W-16303
0 50 5
GAHMA (CPS)
150 -- 40
100 - 30
20
a0 0
10
- 501
50
0 40
100-
50 0
0 0
- 50
-20
- 100
--40
- ISO
- 200 - 60
-250 -
--80
- 300 -
- 100
-350 -
-400---
-450 -
-140
-500 -
--160
-550
--180
- 600 -
-650 -20
-700-
-220
-750 -
-240
- 900
- 850 -260
-900 -
-280
-950 -
S -300
-1000
-1050 - -32
-1100-
-340
-1150 -
-380
-1200 -
-1250 -400
BULLETIN NO. 68
Table 1. Units mapped in this study. Map types are structure contour (SC) and isopach (I).
Lithostratigraphic Units Map types Hydrostratigraphic Units Map types
Hawthorn Group SC, I surficial aquifer system I
intermediate aquifer system / c,
Peace River Formation SC, I intermediate confining SC, I
intermediate confining unit
Bone Valley SC, I Flonridan aquifer system overburden I
Member
Arcadia Formation SC, I Floridan aquifer system SC
Tampa Member SC, I Upper-Floridan aquifer system I
Nocatee Member SC, I Middle Floridan confining unit SC
Suwannee Limestone SC, I
Ocala Limestone SC, I
Avon Park Formation
SC
(e.g.,Evans and Hine, 1991; Scott,
Missimer, 2001).
Hydrogeologic framework studies that
the southwestern Florida region include
1997;
include
Gilboy
(1985), Johnston and Bush (1988), Miller (1986),
Ryder (1985) and Reese and Richardson (2008).
Maps depicting the thickness and extent of the
Floridan aquifer system (FAS), the "intermediate
aquifer" and intermediate "confining beds" include
Buono and Rutledge (1978), Wolansky et al.
(1979a), Wolansky et al. (1979b), Wolansky and
Garbode (1981), Corral and Wolansky (1984) and
Miller (1986). Allison et al. (1995) present a map
of the top of rock of the FAS in the Suwannee
River region, located along the northeast part of
the SWFWMD study area. Meyer (1989) provides
a comprehensive characterization of the
hydrogeologic framework of southern Florida.
Spechler and Kroening (2007) present a
comprehensive study of Polk County hydrology.
Reese (2000) and Missimer and Martin (2001)
present the hydrogeology and water quality of the
FAS in Lee, Hendry and Collier Counties.
Statewide hydrochemical characterizations of
the upper FAS have focused on aquifer-system
mineralogy and processes that led to observed
native groundwater chemistry (e.g., Plummer,
1977; Sprinkle, 1989), and hydrochemical facies
(Katz, 1992). Upchurch (1992) characterized not
only hydrochemical facies, but also naturally
occurring and anthropogenic constituents in the
FAS. Other studies that focused on regional
aspects of FAS hydrochemistry (i.e., salinity,
solute transport and dolomitization) include Back
and Hanshaw (1970), Cander (1994, 1995),
Hanshaw and Back (1972), Jones et al. (1993),
Maliva et al. (2002), Randazzo and Zachos
(1984), Sacks (1996), Sacks and Tihansky
(1996), Steinkampf (1982), Swancar and
Hutchinson (1995), Trommer (1993), and Wicks
and Herman (1994, 1996). Budd et al. (1993),
Budd (2001, 2002) and Budd and Vacher (2004)
have studied in detail the role of permeability,
compaction and cementation in FAS carbonates
of southwest Florida. An overview of surface-
water and groundwater hydrology is provided by
Wheeler et al. (1998). In contrast to these regional
characterizations, Tihansky (2005) identified the
complex relation between water quality,
groundwater flow patterns and structural
heterogeneity within the FAS in northeastern
Pinellas County by employing diverse
hydrogeological and geophysical analyses.
Hydrochemical studies of the intermediate
aquifer system/intermediate confining unit
Plate 33.
T27S ITE8S
T22E T21E
Cross section: DD-DD' Hillsborough and Manatee Counties
TEBS ITE9S
T29S IT30S
T30S IT31S
T31S IT32S
SOUTH
T32S IT33S DD/
5 SOUTH FORK
do LITTLE MANATEE g
5 RIVER
W-7032
UDSC
M-R TAMPA MB
MRS OF
MR' RCADIA FM,
M,R
,s SUWANNEE
LIMESTONE
MR
M "
M -
M ~OCALA -
m
_ LIMESTONE
M FMI
AVON PARK ^\
FORMATION -'
HORIZONTAL SCALE
MILES
0 1 2 3 4 5
0 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGGERATION IS APPROXIMATELY
126 TIMES HORIZONTAL SCALE
150 -- 40
100 - 30
20
50 -
10
0 0
10
- 50
FEET METERS
ru. BED C PEACE RIVER
p pN F FORMATION
SchT
(SEE TEXT FIGURE 9 FOR EXPLANATION
OF HATCH PATTERNS)
r,p,L,S
pL
pL
p,M
p,M ,
c. ARCADIA
p:,,S,Ch,M
:PHMCh,S
p,C,D,M
p,D,T,M
No SPL
MSR
M:R 0 SUWANNEE
CAM LIMESTONE
SR
T,M
M
M
M
M
MIQ DCALA
CMQ LIMESTONE
Q,S,L
S RS AVON PARK
L:S FORMATION
ROMP 39
W-16740
DV-i ROMP 49
W-16576 W-16456 0 100 200 300 400 500
I I I I _ _
0 100 200 300 400 500 UDSC... .. GAMMA(CP) -" HH
GAMMAPGAMMA (CPS)
,*Sh <....uf sc p T
CS IC PSh L
: : : ,S * :.-..:.-..-...-......-.- P. L
-----------
-----------
.....................
-----------
-----------
T.D.' -1575' BLS
NORTH
DD
- 40
- -120
-4500 -
140
- -160
- -180
-650 1-2000
150 -- 40
100 - 30
20
50 -
10
0 0
10
- 50 M
FEET METERS
- 200 - 60
0 125 250
GAMMA (API)
0,
P.C
PCIp
pr
pC
Sp
P .
cp
pe
.P SIP
.PT >
C,p
Pp,P
p,C,M
P;3.D)
PC,C,,D
Pp.c
P PCCh
P.CM
p,CH,,Ch
P~ C
C,Chp,P
M
L,C,M
L,C,M
CM,L,D
D,Ch,M
M,S,C,T
M,C,H,T,R
CM
CMH
MC
M
M
M
M,D
M,C,O
M
M.C
MD
M.D
M 3)ca
M.D.C.O
MD
M
M
D,M
M
M;:5,R,T
D,M,D
MD
MID
M,B),p
M D
M,p
MID
M
MD.p
0
DM,D
D:1
-850 -2g60
-850o -60
- 900 -
-950 -
- -280
- 900 -
-950-
- -280
MID
40h, TAMPA MBR.
RD:C OF
R.D ARCADIA FM.
1H
RAM \~-
:RAM 1 i
RD,RM / -^
RAM
RAM
R'S'C^X--.SUVANNEE ^^~
LIMESTONE
M M
RM
R.M ^- ^
R,M ^- _
R.M ^ ^
R,M
R.M :13,M
R.M
RAC OCALA N
M LIMESTONE
M
M M
M
RM ^
D ^
RMD
R M
0
R,
H0
H.O AVON PARK
FORMATION
M
M.L
1 . : . .
-o . . . .
--JA
-250 -
- 300 -
- 350 -
- 400 -
- 450 -
-500 -
-550 -
- 600 -
-650 -200
T.D.I -1695' BLS
- 700 -
-750
- 800-
WEST Plate 17: Cross section: N-N' Sarasota and Manatee Counties EAST
N N'
R17E RISE ADD 1-75 R18E R19E R19E R20E R20E R21 E
BEE D RD BRIDGE a
RAILROAD ROAD EXTENSION -
Do I LAKE0
5 SARASOTA COW PEN ID F
-i SLUJGH ATUM SAWGRASS 5 -
IDa r D
- FEET -IS TR 6-1 TR 6-3 ROMP 22 ROMP 23 2 HET-iS
W-14882 V-14872 W-16783 W-14382 9 100 200 30s
20 0 50 100 GAMMA (CPS) 20
0 00 GAMMA (CPS) GAMMA (CPS)______
o UDSS. np.H.p,H C
0 Sh < UDSPEACERIVER PEACE RIVER--
SPFORMATIONT M,p, FORMATION
-,50 P CP, P p,D,LC 50 -
20.pPM DC - 20
-. s AR CAD IA ::p.R N o h ||- -- -
100 - C ,pPC 100 0
S. pt TION- CCHh* ,P I|
4-0 ,PhPARCAMARCADIAp 40
.o50 ; i D P LIT DNE TAMP MEMBE : ::..: ,M O IA MTON p.M -o50 -
,p, NO SPLC OFRAARCAFORMATION FORMATION pP.s-
DC -,C IDPcDR
- 200 6D PIP 4DD 60
-a0 i F.M.I.M ,,Ch,R
FORMATION
D I IP
SN C TAMPA LIMEMSTONER
SL ESTNE -16 0- o
D -1 0 MEMBATIOFRT,,hp -1
- 400 OF/ARCADIA __ARAIA "sB s -- 600 -
- 70 G L F MEIUM COARSE_ R M~ ~ 0 -
E 0 ORGAICS L LIMESTONE OCALA
-S-OD CONFINING UNIT R SPAR A HEAVY MINERALS LIMESTONE D D MR R -
FRMATIN FORMATION.-I
A, MR EDI FLORIDAN 0 QUARTZ m Y MGN G Y
- I50- D--20 COARSE EA ANHYIRITE Py PYRITE S R D -50---260
UNTERNEDDED LOESTONE AND DOLOSTOPC LIMECTh CHERD
- D MR UR LR -B -120
D-020
SILT FORE MEDIUM COARSE
-50 40 s -- A -M I -10
-140 PAM pCRMRC -D
-150 -3200 KIMETERS D -50- -30
VERTICAL EXAGGERATION E I NS -L S MRD
-00 LIEST TIMES NERIZONTAL SCALENE MD -0 -
-"-30 ,UFC L$ ADLYM,RMD --340
-340MDRo FORMATI-34
-1150 -
-U50 -
BULLETIN NO. 68
Wales Ridge contains a very thick sequence of
permeable Pliocene-Pleistocene sediments (as
much as 350 ft [107 m]; see also Surficial
aquifer system, p. 53) overlying variably thick
clays of the Peace River Formation. In the
southern part of the Ridge, depth to carbonate
rocks exceeds 325 ft (99.1 m) BLS.
Morphology of the eastern flank of the Lake
Wales Ridge was likely controlled by high-
energy shoreline currents throughout the
Pleistocene (and perhaps the late Pliocene) as
indicated by the sharp topographic relief on the
eastern side of the Ridge. The presence of
discoid quartz pebbles in these sediments
(Cypresshead Formation) also indicates a high
energy depositional environment (Tom Scott,
personal communication, 2004). In contrast, the
western side of the southern part of the Ridge is
flanked by less pronounced topographic relief on
the Polk Upland and DeSoto Plain.
The general topographic relief of the
southern part of the Lake Wales Ridge mimics
that of the emergent part of the Florida Platform
with a steep shelf slope along the east and a
broad gentle slope to the west. Along the
southern margin of the Ridge (Figure 7), subtle
topographic ridges that trend toward the west
bear remarkable resemblance to the southern
Florida peninsula and the Florida Keys
suggesting that paleo-longshore and ocean
currents (e.g., loop current) that existed during
the Plio-Pleistocene are similar to those of
present day. Petuch (1994) referred to this area
as the Caloosahatchee Strait.
Sinkholes
In addition to paleo-sea levels and ocean
currents, karst processes have sculpted the
landscape of southwest Florida. Sinclair et al.
(1985) mapped four types of sinkholes in the
SWFWMD: 1) limestone dissolution: slow-
developing, funnel-shaped with a growth rate
similar to the rate at which the carbonate rocks
dissolve, overburden is thin; 2) limestone
collapse: forms abruptly and overburden is thin
3) cover- subsidence sinkholes: gradual
formation and generally small diameter, where
overlying sands infill limestone dissolution
cavities, overburden is greater than 30 ft (9.1 m)
thick; and 4) cover-collapse sinkholes: sudden
formation and relatively large in diameter,
forming upon a breach of clayey material
overlying a cavity, overburden is greater than 30
ft (9.1 m) thick. These sinkholes significantly
contribute to interaction between surface and
groundwater, intra-aquifer and inter-aquifer
communication (e.g., Tihansky, 1999) and the
vulnerability of aquifers to surface sources of
contamination (Arthur et al., 2007).
Plate 3 reflects the distribution of closed
topographic depressions (CTD) throughout the
SWFWMD region. This map is based on a 15 m
(49.2 ft) resolution digital elevation model
(DEM) produced by the FDEP-FGS in
cooperation with other FDEP programs and
Florida's water management districts. While not
all CTDs reflect karst features (i.e., paleodunes,
etc. may also be included), this depression
coverage provides a good approximation of
sinkhole distribution patterns within the study
area. The coverage, however, does not reflect
the tens of thousands (if not more) of buried
sinkholes detectable by means of surface
geophysical surveys (e.g., Wilson and Beck,
1988; Moore and Stewart, 1983), nor does it
include small karst features detectable by
LIDAR or sinkholes that formed since the USGS
topographic maps were last updated.
Springs
Springs predominantly occur in the northern
two-thirds of the study area (Figure 6).
Submarine springs occur offshore of Lee County
and between Pinellas County and Citrus County
(Ryder, 1985; DeWitt, 2003). Five of Florida's
thirty-three first magnitude springs (>100 ft3/sec;
>2.83 m3/sec) occur within the study area: Kings
Bay Springs Group, Homosassa Springs Group,
Chassahowitzka Springs Group (all in Citrus
County), Weeki Wachee Springs Group
(Hernando County) and the Rainbow Springs
Group (Marion County) (Champion and Starks,
2001). The Coastal Springs Groundwater Basin
(Knochenmus and Yobbi, 2001) encompasses
parts of Citrus, Hernando and Pasco Counties
and includes three of the five first magnitude
springs. The Coastal Springs Groundwater
Basin is made up of four sub-basins: Aripeka,
Weeki Wachee, Chassahowitzka and Homosassa
Springs. These groundwater sub-basins
comprise part of the total recharge area for these
springs. Surface water basins comprise the other
component. As defined and described in DeHan
BULLETIN NO. 68
A meaningful comparison of the IAS/ICU
potentiometric surface (Duerr, 2001) with that of
the FAS is qualitative at best (see discussion
starting on page 62). A more accurate, although
site-specific method for assessing the
recharge/discharge relation between the
IAS/ICU and FAS is to compare water levels in
nested wells, many of which are located at
District ROMP sites. As noted above, Miller
(1986) subdivided the FAS into the Upper
Floridan aquifer (UFA) and the Lower Floridan
aquifer (LFA). The UFA is the principal source
of groundwater throughout the study area except
for Charlotte County, where only 20 percent of
total w ithdia% als originate from the UFA (based
on data from 2000 as compiled by Marella,
2004) due to naturally poor water quality. The
most productive units of the UFA are located
within the Avon Park Formation, Ocala
Limestone and the Suwannee Limestone (Ryder,
1985).
A highly permeable facies of the FAS,
referred to as the "Boulder Zone" (Kohout,
1965), is characterized by cavernous, fractured
dolostones with very high transmissivities (Puri
et al., 1973). Vernon (1970) reported "Boulder
Zone" facies throughout the Florida peninsula.
More recently, however, this hydrogeologic
facies has been recognized as discontinuous and
found to be limited to the southern third of the
Florida peninsula (Miller, 1986). The facies
does not occur within the same lithostratigraphic
unit throughout its extent (Miller, 1986).
Maliva et al. (2001) report occurrences of
"Boulder Zone" facies in the Early Eocene
Oldsmar Formation in Charlotte, Lee and Collier
County injection wells. This facies has been
reported to occur at depths shallower than -1300
ft (-396.2 m) MSL in Charlotte County (Maliva
et al., 2001), which corresponds to Avon Park
Formation carbonates. In the southernmost
peninsula, the facies occurs within the Paleocene
Cedar Keys Formation as well as the Eocene
Avon Park Formation and Ocala Limestone
(Puri and Winston, 1974).
Wolansky et al. (1980) mapped "the highly
permeable dolomite zone" of the Avon Park
Formation throughout the southern two-thirds of
the District. These well-indurated dolostones
are commonly fractured and contain large
dissolution channels. The zone occurs -100 ft
(~ 30.5 m) below the top of the Avon Park
Formation in the central part of the study area
and ~ 400 ft (~ 122 m) below the Avon Park
Formation surface in the southern region. The
SAS and IAS/ICU generally provide
confinement of the UFA (Berndt et al., 1998)
except for areas in the northern region where the
UFA may be unconfined and where karst and
paleokarst promote inter-aquifer connectivity.
Hydrogeologic conditions vary considerably
between the northern and southern regions
depending on the degree of confinement.
The interpolated surface of the UFA ranges
from greater than 75 ft (22.9 m) MSL along the
Brooksville Ridge to less than -825 ft (-251 m)
MSL in southern Charlotte County (Plate 58).
Locally, maximum elevations exceed 130 ft
(39.6 m) along the Brooksville Ridge (W-14917
[ROMP 109], Plate 7). A map of overburden
thickness provides a different perspective on the
depth to the top of the UFA (Figure 31). This
map, developed by subtracting the UFA surface
from a 15 m (49.2 ft) resolution DEM (Arthur et
al., in review), allows comparison of the aquifer
system to geomorphic features. For example,
note the thin overburden along the Brooksville
Ridge compared to the Lake Wales Ridge, as
well as the maximum overburden thickness of
-900 ft (-274 m) in Charlotte County.
The base of the UFA occurs within the lower
Avon Park Formation, where vertically and
laterally persistent evaporite minerals (gypsum
and anhydrite) are present in the carbonate rocks
(e.g., Ryder, 1985; Hickey, 1990; see Middle
Floridan confining unit [MFCU], p. 75, for more
information). Thickness of the UFA, calculated
as a "grid difference map," ranges from less than
300 ft (91.4 m) to more than 1500 ft (457 m;
Figure 32). Regional subjacent confinement of
the UFA is comprised of the MFCU where
present. Examples of basal UFA confinement
are represented in several cross sections (e.g.,
Plates 7, 9, 21 and 31). Note, however, that
Miller's (1986) delineation of overlapping
MFCU units by default suggests that the base of
the UFA in these areas is a complex
discontinuous surface. This aspect of the UFA
is described in more detail in the next section.
BULLETIN NO. 68
the Anderson-Darling test for normality. In the
Anderson-Darling test, the A2 value is the test
statistic for normality; if the probability (P-
value) is greater than 0.05, the data are normally
distributed. Graphical summaries of the
hydrogeological data include histograms, box
plots and 95 percent confidence interval range
charts. The histograms include a log-normal
curve fit for all parameters except for the
porosity data and SAS vertical hydraulic
conductivity. The vertical (y) axis on the
histograms reflects the total number of analyses
(N), which are listed in each statistical summary.
Units for each parameter are listed in the figure
header. The horizontal (x) axis of the box plots
corresponds to the histogram x-axis. Asterisks
in the box plots denote statistical outliers.
Surficial aquifer system
The surficial aquifer system (SAS) is
predominately comprised of Late Pliocene to
Holocene sediments and is contiguous with land
surface. This hydrostratigraphic unit occurs
throughout the study area, with the exception of
two hydrogeologic settings: 1) where an
unobstructed vertical hydraulic connection exists
between surficial sediments and the FAS (e.g.,
unconfined FAS) and 2) where the very low-
permeability sediments of the Hawthorn Group
(e.g., Peace River Formation) locally occur at or
near land surface (e.g., SAS absent and FAS is
confined). This latter setting occurs in the
central and southern Polk Upland physiographic
province (Figure 6). The extents of either of
these settings are too localized or disturbed by
mining to delineate accurately within the scale
and scope of this project. The SAS generally
consists of unconsolidated quartz sand with
variable amounts of shell, clay, phosphate and
organic material. Shell content in the SAS
increases significantly toward the southern part
of the study area (Vacher et al., 1993; see also
"UDSS" comprising the SAS in the
southernmost cross sections [e.g., Plates 18,
19]). Excluding the ridges, thickness of the SAS
averages -30 ft (-9 m). Along the Lake Wales
Ridge in the southeastern part of the study area,
SAS thicknesses range to more than 300 ft (99.4
m) (Plates 26 and 55). In the southern region,
the areas with relatively thick SAS generally
correspond to localities where the permeable
upper Tamiami Formation sediments are
included within the SAS.
The SAS is delineated in areas where
laterally extensive, sufficiently confining clayey
sediments of the IAS/ICU occur beneath
unconsolidated surficial sediments. In parts of
the northern region, the SAS locally may
directly overly the FAS. Iron-cemented zones
("hardpan") and intermittent basal clays may
result in a "perched" water table or local SAS-
like unit. On the other hand, basal confinement
breached by sinkholes or fractures precludes
characterizing much of the northern region as a
laterally extensive and functional SAS due to
lack of regional hydraulic continuity. In this
hydrogeologic setting, delineation of the SAS
becomes subjective. To account for such areas,
a hachured pattern is included on Plate 55 to
reflect "discontinuous basal confinement of the
SAS." It is noteworthy that this subjective
delineation could also be applied to the northern,
significantly karstified part of the Brooksville
Ridge; however, in recognition of available data
and to maintain consistency with the IAS/ICU,
the SAS is delineated in this area.
Groundwater w ithdrawals from the SAS are
minimal compared to that of the IAS/ICU or
FAS. Based on data from Marella (2004), the
SAS yielded between 1 percent and 5 percent of
total groundwater withdia%%als in Charlotte,
Citrus, Levy, Marion, and Sumter Counties
during 2000. In Lee County, the SAS comprised
more than 55 percent of total w ithdiaals
(Marella, 2004). Each of the remaining counties
in the study area withdrew less than 1 percent
groundwater from the SAS (Marella, 2004).
Throughout the study area, the local water
table mimics topography (Sepulveda, 2002;
Arthur et al., in review). Elevation of the water
table varies widely throughout the study area,
ranging to more than 175 ft (53.3 m) MSL
(Arthur et al., in review). Along much of the
Lake Wales Ridge, such as in the Intraridge
Valley (Figure 6) the water table is often less
than 10 ft (3.0 m) below land surface. The water
table in other parts of the Lake Wales Ridge, as
well as other upland areas, can exceed 50 ft
(15.2 m) below land surface. Movement of SAS
FLORIDA GEOLOGICAL SURVEY
Limestone as three megacycles each composed
of several shallowing upward cycles: 1) the
outer ramp characterized by skeletal-rich, grain
supported to muddy, open-marine, shallow and
deep-ramp facies, 2) shallow ramp facies -
composed of wave dominated skeletal banks and
shoal complexes and shallow and deep subtidal
lagoonal deposits, and 3) restricted marine -
deposition in a restricted marine, brackish
lagoon and mud-rich tidal flat environment.
Oligocene-Pliocene Series
Hawthorn Group
Hawthorn Group sediments range in age
from mid-Oligocene (Brewster-Wingard et al.,
1997) to Early Pliocene (Scott, 1988; Covington,
1993; Missimer et al., 1994) and generally
consist of phosphatic siliciclastics (sands, silts
and clays) and carbonates. Trace amounts of
pyrite occur throughout the Hawthorn Group
section in southwestern Florida (Lazareva and
Pichler, 2007). In the study area, the Hawthorn
Group consists of the Arcadia Formation, the
Peace River Formation and undifferentiated
sediments, all of which generally lie
unconformably above the Suwannee Limestone
and unconformably beneath undifferentiated
Pliocene and younger sands, shells and clays.
Benthic foraminifera characteristic of the
Hawthorn Group include Archaias sp., Sorites
sp., Amphistegina lesson and Cassigerinella
(Cassidulina) chipolonsis (Figure 15).
Predominant formational members of the
Hawthorn Group present in the study area
include the Tampa and Nocatee Members
(Arcadia Formation) and the Bone Valley
Member (Peace River Formation). The extent of
all Hawthorn Group sediments (Plate 43)
generally includes those areas where
undifferentiated confining beds of the IAS/ICU
(Plate 56) are present beyond the mapped extent
of the Arcadia and Peace River Formations
(Plates 45 and 51, respectively) such as Marion
County, Pinellas County and central Pasco
County. The maximum observed thickness of
the Hawthorn Group exceeds 825 ft (251.5 m) in
south-central Charlotte County (Plate 44).
The Hawthorn Group was deposited in a
shallow marine to nonmarine fluvial and deltaic
environment that prograded over the older
carbonate platform (Scott, 1988; Ward et al.,
2003). Similar to other units mapped in this
study, the top of the Hawthorn Group can
demonstrate variable local relief, as exhibited by
its irregular erosional and karstic surface (Berndt
et al., 1998). Based on mineralogy of Hawthorn
Group sediments, incipient stages of
phosphogenesis occurred during the Late
Oligocene during deposition of the lower
Arcadia Formation (Brewster-Wingard et al.,
1997). Sea-level fluctuations strongly
influenced deposition and exerted a major
control on phosphogenesis and sedimentation
(Riggs, 1979a, 1984; Compton et al, 1993).
During sea-level transgressions a large part of
the Florida platform was submerged.
Meandering of the Gulf Stream resulted in
upwelling over the platform, which increased
organic productivity and enhanced
phosphogenesis in the shallow waters of the
shelf (Compton et al, 1993). Maximum
phosphorite precipitation is thought to have
occurred in shallow-water coastal and nearshore
shelf platforms or other submarine topographic
highs (Riggs, 1979a). Sea-level fluctuations and
ocean currents facilitated transport, deposition
and concentration of phosphate grains (Scott,
1988, 1992b). Primary depositional features
such as graded bedding and cross beds provide
evidence of this high-energy depositional
environment (Scott, 1988). The height of
phosphate deposition and reworking was
synchronous with Peace River Formation
deposition (Middle to Early Pliocene).
Arcadia Formation
The Upper Oligocene (Brewster-Wingard et
al., 1997) to Middle Miocene Arcadia Formation
is comprised of a yellowish gray to white,
variably sandy (quartz and phosphorite)
carbonate with interbeds of siliciclastic-
dominant sediments. Although limestone is
present, dolostones are most common, ranging
in grain size from microcrystalline to medium
sand, with the more coarse material being
sucrosic. Minor clays and chert beds (some
comprised of silicified clay) also occur
(Upchurch et al., 1982; Scott, 1988). Porosity
types include intergranular and moldic.
NORTH
G T33S T34S
MCMULLEN
CREEK
I a
Plate 36: Cross section: GG-GG' Manatee, Sarasota, and Charlotte Counties
T34S T35S
T36S T37S
T37S T38S T38S T39S T39 5 T40S
SOUTH
OSCAR
TR 8-1
W-15826
TR 7-2
W-17057
0 50 100
GAMMA (CPS)
pT ARCADIA
p|R. | FORMATION
AM TAMPA MBR,.
S ARCADIA FM,
| t SUWANNEE
OPy LIMESTONE
DCALA
LIMESTONE
MR
M,R 0
M,D
SAVON PARK
i FORMATION
S i I I I I I I
0 1 2 3 4 5 6 7 N
KILOMETERS
VERTICAL EXAGGERATION IS APPROXIMATELY
98 TIMES HORIZONTAL SCALE
0 50 100
SC GAMMA (CPSI
C~p
ChQp,C,TPy
OPp pC FORMATION
Tp,,Pch
,P,pPCh
.M.p TAMPA MEMBER
P ARCADIA
p FRMATI
NOPL
Q,C,R
,Mp TAMPA MEMBER
M ' C L IM E S TD N E
MNO
A
T.D. = 1713' PLS
SA-1
W-17452
TR 6-3
W-14872
010 i001 PEACE RIVER FM,.
USE C GAMMA (CPS) : 0
ARCA.IA.- .
LA
L pC,P
MP M
CM
AARCADIA L
C-
RR ChP
Ch,p,P. TAPAMMPR
FML
.1R:' h: ,h
FORMATIONE
20 PL CP
QOCALP
L,p,P,M M,
Q,P, ,CM ,Cp S
QLIPMTMN
- - - - Q,p,p,
Q~pPM ,p
p~gOSh,
ROa AVOFON P-K
pQ,R,p -- ARCAM
ORQRA I R
T C.=12 0 f BLS E"B
RQm
pR,Sh
Q]
Sh LIMESTONE
R V NPR
RFOMAIO
T O, 20 L
ROMP 20
W-17087
TR 5-1
W-15168
60 20
50 -
20
1 0
20
30 -_ 10
FEET METERS
20
INTRACOASTAL
WATERWAY
RED I ALLI
CREEK
TR 4-1
W-17488
0 100 200
GAMMA (CPS)
a 25 50
GAMMA (CPS) 0 200 400 UISC
L PEACE RIVER FM, I I
GAMMA (CPS)
Sp,',L,' PEACE RIVER FM,
,M,sh ARCADIA
P FORMATION
p.C h.
P PIP
^ T.C
,PSh / ^ M,D,0,P P"
pMOR LO TAMPA MEMBER p
M FORMATION
SM::pFDRMATIDN
T Mh, C ,C ,L,
| \ \\\ SUWANNEE
LIMESTONE
.P M,DR AVONP
"M MCRD FORMAT
IM,D,C,D
MD (SEE TEXT FIGURE 9 FR EXPLANATION
O F HATCH PATTERNS)
T,D, = 1439' BLS
SOUTH
T40S TI 41S GG
OYSTER
CREEK
GOTFRIED ROCK
CREEK CREEK
TR 3-3
W-15683
r ~UDSC g
p' PEACE RIVER
:,, FORMATION
:ARCADIA
FORMATION
PD
pMR
;;M:R
M, R
CS,p
STAMPA MEMBER
,,MR [IDF
SARCADIA -
D ^
L ARCADIA
:RC FORMATION
R
MR
M,RL
SUVANNEE
LIMESTONE
AARK
FION
,,M.R,Ch C
4,R / ^
0 SPL ^^
SUWANNEE I
LIMESTONE
PARKi
TION
0 200 400 50 -
GAMMA (CPS)I
0 75 150
GAMMA (CPS)
p,I,T,C,,O -
T,0 USDC
p,P,C PEACE RIVER
CPA
0,LP,p,C
Cp
c,aP,p
LpCo,
Lp
L FORMATION
L,P,a
C,A0pL ARCADIA
PEL FORMATION C
OBp.C,O TAMPA MEMBER
P OF
p, ARCADIA
pOODCh FORMATION
Q,p
g,M,p -*
PD
C,QD ^ FORMATION
p
5 p.
SUWANNEE
LIMESTONE
D0
OC ALA
D LIMESTONE
AVON PARK
FORMATION
pSh
p.MT.N.
pp,.S
pL,T
AN.O
pT.M
,T,L
p,Ps
p,L,T
NH.C
pT1 L
T ,H~
TMR
T.D.110 LS
. ............... ..........
- 850 -260
-200 60
- 850 -260
-1050 -+ -320
- -340
60 20
50 -
40
30 10
20
10-
0 0
20 1
3 0 -E0
FEET METERS
- 200 + A
-1050 +- -320
- -340
Plate 12. Cross section: I-I' Pinellas and Hillsborough Counties
R16E R17E R17EI RO1 E R RI R 19E RR19E R20E R20E R21E
M I r III |t I BRANCH RI|ER
150 - 40
100 - 30
20
50 -
10
0 - 0
0 10
- 150 -
150
S40
100 -
O
50
0 0
- 50 -
- 100 -
- 150
- 250
- 300
EAST
I'
R21E I R22E
W-7032
50 - 40
50 40
- 5R
FEET METERS
150
40
AVON PARK
FORMATION
HORIZONTAL SCALE
MILES
0 0.5 1 2 3 4 5
I I II 1I
00.51 2 3 4 5 6 7 8
KILOMETERS
[VERTICAL EXAGGERATION IS APPROXIMATELY
116 TIMES HORIZONTAL SCALE
HATCHING PATTERNS
-LIMESTONE
FINE MEDIUM COARSE
DOLOST'NE
FINE MEDIUM COARSE
--INTERBEDDED LIMESTONE AND DOLOSTONE---
FINE MEDIUM COARSE
CHERT SHELL BED GYPSUM
EXPLANATION
I SURFICIAL
AQUIFER
SYSTEMN
S FLORIDAN
M AQUIFER
SYSTEM
NNN IT
COMMENTS
M MICRITE T SILT
S SAND C CLAY
P PHOSPHATE GRAVEL Sh SHELL
p PHOSPHATE SAND D DDLDSTONE
0 ORGANIC L LIMESTONE
R SPAR H HEAVY MINERALS
I IRON STAIN NO SPL NO SAMPLE
0 QUARTZ 0 GYPSUM
A ANHYDRITE Py PYRITE
Ch CHERT
TO.' -1683' NGVD
WEST
I
R15E R16E
W-12943
N. LAKE TARPON W-7795 DUNDEE W-3428 PEBBLE CREEK
W-50149 W-50143 W-50148
UDSC
M.Ch
M,Ch
MS
MT,R,S
: 'PYCh
M
M,D
M.D
M.D
M.Ch
M,Ch
SUWANNEE
LIMESTONE
AVON PARK
FORMATION
GRAVEL
SAND
SILT
CLAY
- -340
-U50
-1150
FLORIDA GEOLOGICAL SURVEY
LaRoche, J.J., 2004, ROMP 35 West DeSoto Monitor well site DeSoto County, Florida Final Report
exploratory coring monitor-well construction aquifer performance testing: Brooksville, Southwest
Florida Water Management District, Resource Data Section, Resource Conservation and
Development Department, 44 p., plus appendices.
Law Environmental, Inc., 1989, Results of exploratory/monitor well construction and testing, Knight
Trail Park: report prepared for the Florida Department of Environmental Regulation, file no.
UC58-125241.
Lazareva, 0., and Pichler, T., 2007, Naturally occurring arsenic in the Miocene Hawthorn Group,
southwestern Florida: Potential implication for phosphate mining: Applied Geochemistry, v. 22,
p. 953-973.
Lee, R.A., 1998, Coastal springs project drilling and testing report freshwater coastal monitor wellsites
Pasco, Hernando and Citrus Counties, Florida: Brooksville, Southwest Florida Water
Management District, 9 p.
Levin, H.L., 1957, Micropaleontology of the Oldsmar Limestone (Eocene) of Florida:
Micropaleontology, v. 3, p. 137-154.
Lewelling, B.R., Tihansky, A.G., and Kindinger, J.L., 1998, Assessment of the hydraulic connection
between water and the Peace River, west-central Florida: U.S. Geological Survey Water-
Resources Investigations Report 97-4211, 96 p.
Loizeaux, N.T., 1995, Lithologic and hydrogeologic frameworks for a carbonate aquifer: evidence for
facies controlled hydraulic conductivity in the Ocala Formation, West-Central Florida [M.S.
Thesis]: Boulder, University of Colorado, 298 p.
Macfarlane, P. A., 2000, Revisions to the nomenclature for Kansas aquifers: Current research in earth
sciences: Kansas Geological Survey Bulletin 244, Part 2:
http://www.kgs.ku.edu/Current/2000/macfarlane1.html, (January, 2007).
Maliva, R., Walker, C.W., and Callahan, E.X., 2001, Hydrogeology of the lower Floridan aquifer
"Boulder Zone" of southwest Florida, in Missimer, T.M., and Scott, T.M., eds., Geology and
hydrogeology of Lee County, Florida: Durward H. Boggess Memorial Symposium: Florida
Geological Survey Special Publication 49, p. 167-182.
Maliva, R.G., Kennedy, G.P., Martin, W.K., Missimer, T.M., Owosina, E.S., and Dickson, J.A.D., 2002,
Dolomitization-induced aquifer heterogeneity: evidence from the Upper Floridan aquifer,
southwest Florida: Geological Society of America Bulletin, v. 114, p. 419-427.
Mansfield, W.C., 1939, Notes on the upper Tertiary and Pleistocene mollusks of peninsular Florida:
Florida Geological Survey Bulletin 18, 75 p.
Marella, R.L., 2004, Water withdrawals, use, discharge, and trends in Florida, 2000: U.S. Geological
Survey Scientific Investigations Report 2004-5151, 50 p.
McCartan, L., Weedman, S.D., Wingard, G.L., Edwards, L.E., Sugarman, P.J., Feigenson, M.D.,
Buursink, M.L., and Libarkin, J.C., 1995, Age and diagenesis of the upper Floridan aquifer and
the intermediate aquifer system in southwestern Florida: U.S. Geological Survey Bulletin 2122,
26 p.
BULLETIN NO. 68
U.S. Department of Agriculture, Natural Resource Conservation Service, 2002, National Soil Survey
Handbook, title 430-VI, USDA: http://soils.usda.gov/technical/handbook/ (January, 2007).
U.S. Geological Survey, 1990, Water resources data Florida, Water year 1990, Volume 3B, southwest
Florida groundwater: U.S. Geological Survey Water-Data Report FL-90-3B, 241 p.
1998, Water resources data Florida, Water year 1998, Volume 3B, southwest Florida
groundwater: U.S. Geological Survey Water-Data Report FL-98-3B, 323 p.
Vacher, H.L., Jones, G.W., and Stebnisky, R.J., 1993, Heterogeneity of the surficial aquifer system in
west central Florida, in Scott, T.M., and Allmon, W.D., eds., Plio-Pleistocene stratigraphy and
paleontology of southern Florida: Florida Geological Survey Special Publication 36, p. 93-99.
Vernon, R.O., 1951, Geology of Citrus and Levy Counties, Florida: Florida Geological Survey Bulletin
33, 256 p.
1970, The beneficial uses of zones of high transmissivities in the Florida subsurface for water
storage and waste disposal: Florida Bureau of Geology Information Circular 70, 39 p.
Vernon, R.O., and Puri, H.S., 1964, Geologic map of Florida: Florida Bureau of Geology Map Series 18,
scale approximately 1:2,000,000, 1 sheet.
ViroGroup, Inc., 1995, Completion report for Burnt Store utilities class I injection well system Punta
Gorda, Charlotte County, Florida: report prepared for Charlotte County, 55 p. plus Appendices.
Ward, W.C., Cunningham, K.J., Renken, R.A., Wacker, M.A., and Carlson, J.I., 2003, Sequence-
stratigraphic analysis of the regional observation monitoring program (ROMP) 29A test corehole
and its relation to carbonate porosity and regional transmissivity in the Floridan aquifer system,
Highlands County, Florida: U.S. Geological Survey Open-File Report 03-201, 34 p.
Webb, S.D. and Crissinger, D.B., 1983, Stratigraphy and vertebrate paleontology of the central and
southern phosphate districts of Florida, in The Central Florida Phosphate District Field Trip
Guidebook, Geological Society of America, Southeastern Section Annual Meeting, p. 28-72.
Weinberg, J.M., and Cowart, J.B., 2001, Hydrogeologic implications of uranium-rich phosphate in
northeastern Lee County, in Missimer, T.M., and Scott, T.M., eds., Geology and hydrogeology
of Lee County Florida: Durward H. Boggess Memorial Symposium: Florida Geological Survey
Special Publication 49, p. 151-166.
Wheeler, W., Owen, R., and Johnson, T., 1998, Chapter 12-Southwest Florida Water Management
District, in Femald, E.A., and Purdum, E.D., eds., Water resources atlas of Florida: Tallahassee,
Florida State University, 312 p.
White, W.A., 1970, The geomorphology of the Florida peninsula: Florida Geological Survey Bulletin 51,
164 p.
Wicks, C.M., and Herman, J.S., 1994, The effect of a confining unit on the geochemical evolution of
groundwater in the upper Floridan aquifer system: Journal of Hydrology, v. 153, p. 139-155.
Wicks, C.M., and Herman, J.S., 1996, Regional hydrogeochemistry of a modem coastal mixing zone:
Water-Resources Research, v. 32, p. 401-407.
FLORIDA GEOLOGICAL SURVEY
Summary for IAS L (per day)
0.00 0.01 0.02 0.03
95% Confidence Intervals
Mean-
Median-
Figure 26. Statistical summary of IAS/ICU leakance data from Southwest Florida Water
Management District (2006b). Asterisks in the box plot denote statistical outliers.
Summary for IAS Kh** (ft/day)
Anderson-Darling Normality Test
A-Squared 3.07
P-Value < 0.005
Mean 38.481
StDev 53.858
Variance 2900.656
Skewness 2.12027
Kurtosis 4.85107
N 30
Minimum 0.045
L1st Quartile 4.988
0 60 120 180 240 Median 13.200
3rd Quartile 59.125
M axim urn 232.000
95% Confidence Interval for Mean
18.370 58.592
95% Confidence Interval for Median
95% Confidence Intervals 8.684 34.030
Mean- I I 95% Confidence Interval forStDev
42.893 72.402
Median- I S I
10 20 30 40 50 60
Figure 27. Statistical summary of IAS/ICU horizontal hydraulic conductivity data from Southwest
Florida Water Management District (2006b). Asterisk in the box plot denotes statistical outliers.
** calculated from transmissivity and permeable zone thickness.
Anderson-Darling Normality Test
A-Squared 3.70
P-Value < 0.005
Mean 0.003427
StDev 0.008193
Variance 0.000067
Skewness 3.7045
Kurtosis 14.2198
N 16
Minimum 0.000033
1st Q uartile 0.000187
Median 0.000968
3rd Quartile 0.001921
Maximum 0.033425
95% Confidence Interval for Mean
-0.000939 0.007792
95% Confidence Interval for Median
0.000196 0.001759
95% Confidence Interval for StDev
0.006052 0.012680
Plate 20. Cross section: Q-Q' Polk and Osceola Counties
R24EIR25E
R25EIR26E
W EST RAILROAD
Q I
W-50122
W-15601 W-
UNDIFF, SAND
AND CLAY UNDIFF. SAND GAMMA LOG
M 1 5 I AND CLAY NO SCALE AVAILABLE
GAMMA (CPS) GAMMA (CPS)
NO SPL
C,G
C,p,L /
OCALA / OCALA
LIMESTONE LIMESTONE
AVON PARK
FORMATION
EXPLANATION
HATCHING PATTERNS COMMENTS
LIMESTONE
GRAVEL FINE MEDIUM COARSE I SURFICIAL
a AQUIFER
SOLOSTNE ... ... SYSTEM
E FLORIDAN
S. AQUIFER
SYSTEM
SAND FINE MEDIUM COARSE
/-- NTEREEDDED LIMESTONE AND DOLOSTONE--
SILT FINE MEDIUM COARSE
M MICRITE T
S SAND C
P PHOSPHATE GRAVEL Sh
p PHOSPHATE SAND D
0 ORGANIC L
R SPAR H
I IRON STAIN NO SPL
0 QUARTZ G
A ANHYDRITE Py
Ch CHERT
W-50123
-1
zi-r--
CLAY
SHELL
DOLOSTONE
LIMESTONE
HEAVY MINERALS
NO SAMPLE
GYPSUM
PYRITE
V-15E
? p 10 UNDIFF, SAND
GAMMA (CPS) AND CLAY CP >
GAMMA CPS)
NO SPL C.Sh
NO SPL
^-- '-- -------
OCALA
- LIMESTONE
AVON PARK
FORMATION
L
HORIZONTAL SCALE
MILES
1 2 3
1 2 3 4 5
KILOMETERS
L,p UNDIFF, SAND
pLC AND CLAY
p,L.C
c
C,J
C,J,p
C,J,p
AVON PARK
FORMATION
I I7 8
6 7 8
VERTICAL EXAGGERATION IS APPROXIMATELY
59 TIMES HORIZONTAL SCALE
40
100-
0 0
-50
FEET METERS
250 1 0
200 40
R26EIR27E
- 30
EAST
Q'
150 -
100 -
50 -
0
- 50 -
- 100 -
- 150
- -40
W-5892
0o- 0
-50o
FEET METERS
- 200 -+ 60
250 -
200
- -100
-250 -
- 300 -
- 350 -
- 400 -
- 450 -
- 500 -
-550 -
- 600 -
150 -
Sh,P,p
0-
100 -
150
-650 -- -220
- 700 -
-750 -
- -220
CLAY CHERT SHELL BED GYPSUM
- 40
- 200 - 60
- 400 -120
-700 -
-750 -
- -220
-650 -200
-450 -
-500 -
-550 -
- 600 -
50-F
FLORIDA GEOLOGICAL SURVEY
Lithology
For each well in a cross section, a
stratigraphic column was developed to represent
borehole lithology. The columns were based on
either existing descriptions or new descriptions
generated for this report. Hatch patterns depict
primary lithologies in the columns, with
accessory minerals shown on the right of the
columns as text codes. Where space is
available, the cross sections contain an
explanatory legend that defines mineralogic and
lithologic codes and patterns. For those cross-
sections without sufficient space to include the
"Explanation," it is also provided for reference
in Figure 9. Accessory-mineral codes are
generally the same as those used in the FDEP-
FGS lithologic database (FGS Wells). If the
volume of reported accessory sand-sized
minerals exceeds 5 percent, the content is
represented by a stippled sand pattern. If the
amount of accessory sand-sized minerals is less
than 5 percent, or if the amount is not known
based on existing descriptions, the accessories
are listed in the text codes. The mineral text
codes are listed in decreasing order of
abundance if the relative mineral abundance has
been reported.
The degree of detail within each lithologic
column generally reflects the type of material
available for description as well as the degree of
detail in the description. In most cases, more
detailed lithology exists for the cores. The
minimum bed thickness represented on the
stratigraphic columns is 5 ft (1.5 m) due to
graphical constraints. There are several
examples where lithologies and accessory
minerals have been averaged over a 5 to 10 foot
(1.5 to 3.0 m) interval to accommodate this
graphical limitation.
Gamma-ray Logs
Selected gamma-ray logs are plotted to the
right of stratigraphic columns on the cross
sections. These logs are used as a supplement to
delineate formation boundaries and allow
comparison of gamma-ray activity between the
various lithostratigraphic and hydrostratigraphic
units (e.g. Gilboy, 1983; Green et al., 1995;
Scott, 1988 and Davis et al., 2001). Gamma-ray
intensity units, when known, are shown on the
logs (horizontal axis) in counts per second (CPS)
or in American Petroleum Institute (API) units.
Inconsistencies between logs exist due to
different log settings (e.g., time constant, range)
and borehole characteristics (e.g., depth of
casing and lack of caliper logs to determine
sediment wash-out or cavities), making
quantitative comparison difficult. To allow
assessment of the high degree of variability in
the logs and to represent their natural response,
the intensity scales have not been normalized.
The logs are very useful in the identification of
correlative "packages" of gamma-ray peaks and
for comparison of the overall gamma-ray
signature within formational units. Relatively
high gamma-ray activity is generally correlative
with phosphate, organic materials, heavy
minerals and high-potassium clays. More subtle
changes may reflect dolomite and accessory
mineral content. Figure 10 summarizes general
relationships between gamma-ray activity and
mineralogy, the details of which are included in
the discussion of each lithostratigraphic unit (see
I i,ih, i, ogi,, O h', p. 30).
Aquifer Systems
Aquifer systems on the cross sections appear
as hachured brackets on the left of each
lithologic column. Patterns used in the
hydrostratigraphic columns identify the three
major aquifer systems present in the study area,
as well as the MFCU.
Map Development and Data
Management
For wells used in this study, elevations of
lithostratigraphic and hydrostratigraphic units
were recorded in a database that also included
the corresponding FDEP-FGS well accession
number (W-number), well name, comments
about the well, the geologist(s) who made the
determinations and well location (elevation,
latitude and longitude). The unit elevations on
which the maps are based are recorded in feet
BLS; a separate column calculates the elevation
WEST Plate 26. Cross section: W-W' Sarasota, DeSoto, and Highlands Counties EAST
W W/
R22EI R3ERE R2|4E R24EIR25E R26EIR27E R27EI R E RBSE IR29E Seaboard
60 F0kavng Contune 200- 6
o o ROMPRA m6 6CrkRoM 1
-m ROMP 18 ROMP 17 ROMP 16 ROMP 15 W-50105 ROP 14 -7m
E-14383 V-15303 V-14381 /-15801 V-17001
30 CEK-30
S0 so o2 G0A lPS) 1 --
ROP16OM 7RMP16OP 5W5160 5OP1
l Jf
o SCcALE AVAI LA BLNA (CPE) G69MA (CPS) h.
50 -6C040 GAMMA CCPS) N1 SCALEoAVAC.A.l.E $fJCP.T6 uhS 50 -
UD, C I I> -,,,,U'..Cg
P. fEAp PEACE 4 \ CAHD
Pcs CPTA- PACE C
FM...e R ERTAL RIVER ;
-3-0
. DGAPA MAPEACE -
-100 M ,LpTCpT 160
0 CpL~pT- 40
NPRCADIA ARCAIA V L PEACE -1MC0
- 150 p,0C GN4 LGCTs
-IER0 - T60-H-oo -
Np TpLC. TL C ,JJp
-" --- F. L c.Pa --C.. M ~H,CosP' I I
- 40 M S A* *' 'up "L p"TND 5P
PEAC P C DAC IARCAHDIA
RIVERTP,S 100
-1 FMMR -FM.Cp
P6NOCATEE /',-~ .
50 PLP,p,TCH C0
MBR,J4 PE,0.T FM.
-120
DSP 5p p,DTC,HI*
- a 05- L, N-0
R- ,PEEp,TN
SARCADIA MBRNO-CDI
-50 -1A CAORMATIO AMH -1PE0
-- c-. AM ATA P
pTSUMBANNEE
LIMESTONE LIETNl
- --ns MBRE N --
-6oo 0, -s -_
/ TCALA "
:RPso MBR. .,T .FM
- -4 T --
:'BPsI TL--.. u .D A E PL
SR _R-2A D.IIAL
-ae -o o -s--
-LIMESIMSONEs
p FM.
0240 -S24(TR FMPA T0-
-~o~ O E =C 4 AL 8,s -1
-3 - LPMEKTONEI-P 3 -
,D MPGI BD
-PM.C HC4
LIM TNECAL ECI P
-1L0 N.BCT 10
-M IL ELI M E T.N T. A --L
R.4POMCR -4
-5 -360 CL OFHTC ATEN)-350 0
A V O NA K IL M E T E'S'D
-.an -u PARKARKeu
LI-MES TPICEDRICOREAGGRAIONIS PPDA.,-PPP
17TMSHORIZONTAL SCALEco-o-
-400V-NNLLKILOMETERS
-450 I;SPSRRAhS-40---
1 400C -40
-14M P
BULLETIN NO. 68
Crumpacker, D.W., 1992, Chapter 1-Natural Environments: Ecosystems, in Fernald, E.A. and Purdum,
E.D., eds., Water Resources Atlas of Florida: Tallahassee, Florida State University, 280 p.
Cunningham, K.J., McNeill, D.F., Guertin, L.A., Ciesielski, P.F., Scott, T.M. and de Verteuil, L., 1998,
New Tertiary stratigraphy for the Florida Keys and southern peninsula of Florida: Geological
Society of America Bulletin, v. 110, p. 231-258.
Cunningham, K.J., Locker, S.D., Hine, A.C., Bukry, D., Barron, J.A., and Guertin, L.A., 2001, Surface-
geophysical characterization of groundwater systems of the Caloosahatchee River Basin,
Southern Florida: U.S. Geological Survey Water-Resources Investigations Report 01-4084. 76 p.
Cushman, J.A., 1920, The American species of Oi tlh,,i igimi,,t and Lepidocyclina: U.S. Geological
Survey Professional Paper 125-D, p. 39-105.
Cushman, J.A., and Ponton, G.M., 1932, The Foraminifera of the upper, middle and part of the lower
Miocene of Florida: Florida Geological Survey Bulletin 9, 147 p.
Dall, W.H., 1887, Notes on the geology of Florida: American Journal of Science, 3rd series, v. 34, p. 161-
170.
Dall, W.H., and Hamrris, G.D., 1892, Correlation papers-Neocene: U.S. Geological Survey Bulletin 84, 349
p.
Davis, J., Johnson, R., Boniol, D., and Rupert, F., 2001, Guidebook to the correlation of geophysical well
logs within the St. Johns River Water Management District: Florida Geological Survey Special
Publication 50, 114 p.
DeHan, R., (compiler), 2004, Workshop to develop blue prints for the management and protection of
Florida springs: Florida Geological Survey Special Publication 51, CD-ROM.
Deuerling, R., 1981, Environmental Geology Series Tarpon Springs Sheet: Florida Geological Survey
Map Series 99, scale: 1:250,000, 1 sheet.
DeWitt, D.J., 1990, ROMP TR16-2 Van Buren Road monitor wellsite, Pasco County, Executive
Summary: Brooksville, Southwest Florida Water Management District.
2003, Submarine springs and other karst features in the offshore waters of the Gulf of Mexico
and Tampa Bay: Brooksvillle, Southwest Florida Water Management District, 36 p. plus
appendices.
DuBar, J.R., 1958, Stratigraphy and paleontology of the late Neogene starata of the Caloosahatchee River
area of southern Florida: Florida Geological Survey Bulletin 40, 267 p.
1962, Neogene biostratigraphy of the Charlotte Harbor area in southwestern Florida: Florida
Geological Survey Bulletin 43, 83 p.
Duerr, A.D., 2001, Potentiometric surfaces of the Intermediate aquifer system, West Central Florida,
May, 2001: U.S. Geological Survey Open-File Report 01-309, 1 sheet.
81 30'W 81 W
I I
INTERMEDIATE AQUIFER
SYSTEM / INTERMEDIATE
CONFINING UNIT THICKNESS
0 5 10 20 30 40
0 510 20 30 40
Kilometers
Scale: 1:1,000,000
Contour Interval: 75 ft
Projection: Custom FDEP Albers
Miles
Gulf
of
Mexico
0 0
AN 0
m m
- 0 0
00 0
Explanation
m |Study Area
Wells Used
Contours
/ Discontinuous*
_?.? Questionable Extent
Approximate northern limit of IAS
permeable zones
- Water Management Districts
IAS / ICU Thickness (ft.)
*>900
450
* Denotes approximate areas where semi-confinement
is laterally more discontinuous than continuous.
Non-hachured areas reflect variable degrees of
confinement that are more laterally continuous.
I I
81030W 81OW
PLATE 57
7
I
-- U
-q
I
Ol
BULLETIN NO. 68
Figure 13. Selected diagnostic fossils within the Ocala Limestone. Top photo: Eupatagus
antillarum (bar = 2.5 cm; photo courtesy of IP/FMNH). Middle row, left: Nummulites
(Operculinoides) sp. (bar = 1mm; photo courtesy of Jonathan Bryan), right: Rotularia (Spirolina)
vernoni (bar = 1 cm, photo courtesy of IP/FMNH). Bottom: Lepidocyclina ocalana, (bar = 3 mm);
(A) from Cushman (1920), (B) from Rupert (1989).
0 5
Tampa Member
of the Arcadia
Formation Surface
10 20 30 4
Miles
Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 50 ft
Projection: Custom FDEP Albers
Gulf
of
Mexico
00 o
0
o
a7 -
d q
I-
,,' 0)1
0.
L&
Explanation
SStudy Area
Wells Used
Contours
- Tampa Mbr. Extents
-. - Tampa Mbr. Extents
- - Water Management Districts
Tampa Mbr. Surface (ft. MSL)
> 100
E -225
<-350
orange
r
I
I
I - - -
I
I
I
I
r
I
I
I
--I
I
~1
I
I
I
-q
I
II
a
I. -
PLATE 49
I
4.
V.
'4
I
I
I
I
i i
BULLETIN NO. 68
Summary for SAS Kh** (ft/day)
Anderson-Darling Normality Test
A-Squared 0.36
P-Value 0.407
Mean 31.015
StDev 17.940
9Variance 321.854
Skewness 0.17215
Kurtosis -1.27803
N 15
Minimum 6.930
1st Quartile 12.000
12 24 36 48 60 M edian 32.700
3rd Quartile 50.300
Maxim urn 59.000
F ~95% Confidence Interval for Mean
21.080 40.950
95% Confidence Interval for Median
95% Confidence Intervals 14.988 45.706
Mean I I 95%0 Confidence Interval for StDev
13.135 28.294
Median- I p I
15 20 25 30 35 40 45
Figure 21. Statistical summary of SAS horizontal hydraulic conductivity data from Southwest
Florida Water Management District (2006b). ** calculated from transmissivity and saturated
aquifer thickness.
Figure 22. Statistical summary of SAS vertical hydraulic conductivity data based on falling-head
permeameter analyses of core samples completed at the FDEP-FGS. Due to sampling bias, most
samples represent clay-bearing sediments. Asterisks in the box plot denote statistical outliers.
Summary for SAS Kv (ft/day)
0.1 0.4 0.7 1.0 1.3 1.6 1.9
95% Confidence Intervals
Mean I
Median- 0
-0.05 0.00 0.05 0.10 0.15 0.20 0.25
Anderson-Darling Normality Test
A-Squared 7.75
P-Value < 0.005
Mean 0.09749
StDev 0.36853
Variance 0.13582
Skewness 4.7300
Kurtosis 23.0704
N 26
Minimum 0.00002
1st Quartile 0.00004
Median 0.00010
3rd Quartile 0.02215
Maximum 1.85700
95% Confidence Interval for Mean
-0.05137 0.24634
95% Confidence Interval for Median
0.00004 0.00090
95% Confidence Interval for StDev
0.28903 0.50873
Table 2. Generalized correlation chart for units mapped within study area (ages compiled from Covington, 1993, Missimer et al., 1994,
Scott et al., 1994, and Wingard et al., 1994). Numbers are million years before present. Ages are included for reference only and are not
scaled to correlate with all columns in the table. MFCU is Middle Floridan confining unit;
and Caloosahatchee Formations.
Erathem System
Lithostratigraphic
unit
- S U I U
Holocene
- .01 -
Pleistocene
- 1.8
Pliocene
- 5.3
Miocene
-- 23.03-
Oligocene
- 33.9
Eocene
Undifferentiated
sand, shell, and clay
(UDSC)
Bone
Valley Mbr.
m Peace River Fm.
0
Arcadia
Formation
Tampa
-c Member
Nocatee
Member
I Suwannee Limestone
Ocala Limestone
Avon Park
Formation
Hydrostratigraphic
unit
Quat-
ernary
0
0V
UDSC includes the Tamiami, Ft. Thompson
Series
Generalized lithology
Highly variable lithology ranging from
unconsolidated sands to clay beds with trace
amounts of shell fragments
Peace River Formation contains interbedded
sands, clays and carbonates with siliciclastic
component being dominant; variable
phosphate sand content
Arcadia Formation is a fine-grained carbonate
with low to moderate phosphate and quartz
sand, variably dolomitic
Suwannee Limestone is a fine-to medium-
grained packstone to grainstone with trace
organic and variable dolomite and clay
content
Ocala Limestone is a chalky, very fine-to
fine-grained wackestone/packstone varying
with depth to a biogenic medium- to
coarse-grained packstone grainstone; trace
amounts of organic material, clay and
variable amounts of dolomite
Avon Park is a fine-grained packstone with
variable amounts of organic-rich laminations
near top; limestone with dolostone interbeds
typical in upper part, deeper beds are
continuous dolostone with gypsum near base
surficial aquifer
system (SAS)
intermediate
aquifer
system or
intermediate
confining unit
(IAS/ICU)
E Upper
Floridan
aquifer
(UFA)
0
C
'
2 ,*-''MFCU
Plate 18: Cross section: 0-0' Sarasota County
RSE I R19E
R19E I R20E
R21E R R2E
SMYAKKA
RIVER
TR 5-1
W-15168
TR 5-2
W-15636
i 20
50 -
25- -10
0-- 0
- 25 10
FEET METERS
20
0 -
- 50-
- 100 -
- 150 -
- 200 -
-250-
- 300
- 350 -
- 400 -
- 450 -
- 500 -
-550-
- 600 -
0 100 200 300
I I I< I
GAMMA (CPS)
ROMP 19-WAM
W-14787
0 100 200
I I I
GAMMA (CPS)
-"
DUDSS |
C ,,P,S ARCADIA
DPC,P FORMATION
P,p.Ch,S
Chp,P.S
c ps
-ChpP.
PCh,p,P,S
KPp,Ch,S
,S
S,p,T,P L
S.D _
ROMP 18-1
W-14383
ROMP 19X-EAM
W-14717
0 50 100 150 200
GAMMA (CPS)
C ,
:p,P,C,Sh
S,p,C
SpD
S,C,p,R
p,D
s P
S,p.C
S,M,Sh
S,p,M,Sh
S,P,p
"M,Ch
S,p,R --
SID
P,M,L
Ch,SSh TAMF
L,p
L,S.Ch
Sh,p,L
O UDSC
DUD
D.P
P.C
p,C,T
ARCADIA
s,p FORMATION
P
p C
P
Cp,M,RC
S.P.C >
T,D,p,S _;
MR TAMPA
P.M.R MEMBER OF
ARCADIA
P.MAR FORMATION
PM,RC
P,
PR P
p,'
PM,R,L
P.C.M
p,c
p.M,R.Ch
M,R
M.R
NO SPL
M.R
SUWANNEE
LIMESTONE
OCALA
LIMESTONE
------------
M,C,psh aaa
M SSPL
C,S,p,R
M,C,p,S,Ch
D,C,M,p,Ch
M,C,p.S
M,C.p R .H
M,CR, C
RC
M,R,
MDC,R,S
CM,Sp
M,RS
M,R
FINE MEDIUM COARSE
CHERT
LAY
7
SHELL BED GYPSUM
HORIZONTAL SCALE
MILES
0 0.5 1 2 3 4 5
I I I I I I I
0 1 2 3 4 5
KILOMETERS
6 7 8
-1050 -L -320
VERTICAL EXAGGERATION IS APPROXIMATELY
72 TIMES HORIZONTAL SCALE
I
0 50 100 150 200
GAMMA (CPS)
TD=1100' BLS
WEST
EAST
S.h.Ch
-650 -2000
\- -00
- 700
-750 -
- -O
- 850 -260
20
50 -
25- 10
0 10
- 25 10
FEET METER:
20
50
- 50 -
- 100 -
- 150 -
UDSC
PEACE RIVER FM,
ARCADIA
FORMATION
PA MEMBER OF
ARCADIA
-ORMATION NOCATEE MEMBER OF
ARCADIA
FORMATION
-- _ARCADIA FORMATION
COMMENTS
M MICRITE T SILT
S SAND C CLAY
P PHOSPHATE GRAVEL Sh SHELL
p PHOSPHATE SAND D DOLOSTONE
0 ORGANIC L LIMESTONE
M/
R SPAR H HEAVY MINERALS
I IRON STAIN NO SPL NO SAMPLE
Q QUARTZ G GYPSUM
A ANHYDRITE Py PYRITE
Ch CHERT
OCALA
LIMESTONE
AVON PARK
FORMATION
0 100200
GAMMA CCPS)
D,M,p,P
SDS,p,P,M
E D,S,p
D DSp,,S,C,P -
SDL,S,p.M
D
Dp,S SP
iD,p.S,MP
SD,R,PS,p
RD
p,.S,R
EOSPLM
S:1::C:R
P L,tc
P as
C,P
P
S,p.M
RM
C's
M R
M:D
M D
NO SPL
S M
C
M,R
NO SPL
M
M.R
M,R
M,R
M,R
M
NO SPL
MD
M,R ,D
M,R
MISSING
LOG
M,D,R
S M,R
M.D
L,R,M
M,R
-900 -
-950 -
-1000 -
-1050 -L -320
-900 -
-950 -
-1000 -
- 200 + 60
-250 -
- 300 -
- 350 -
- 400 -
-450 -
- 500 -
-550 -
- 600 -
-650 -
- 700
-750-
- 800
-850 -260
EXPLANATION
HATCHING PATTERNS
---~LIMESTONE ,
SSURFICIAL
AQUIFER
m I SYSTEM
iVEL FINE MEDIUM COARSE
INTERMEDIATE
SLOSTNE\ \, AQUIFER SYSTEM
[L .CONFINING UNIT
FLORIDAN
AND FINE MEDIUM COARSE AQUIFER
SYSTEM
--iMTirrD LnrI I TMrOTNr Am nDl RTRNr---E.
LIL
0 -
7
BULLETIN NO. 68
APPENDIX 2. EXPLANATION OF REVISIONS TO FDEP-FGS SPECIAL
PUBLICATION 28 AQUIFER DEFINITIONS
Changes to original Southeastern Geological Society (1986) text are denoted by brackets (additions)
and strikethroughs to reflect definitions applied in this report. Footnotes provide explanation.
surficial aquifer system: the permeable hydrogeologic unit contiguous with land surface that is
comprised principally of unconsolidated to poorly indurated [silici]clastic deposits. It also includes well-
indurated carbonate rocks [and sediments], other than those of the [FAS] Floridan aquifer system where
the Floridan is at or near land surface. Rocks [and sediments] making up the [SAS] surfieial- aquifer
system belong to all or part of the upper7 Miocene to Holocene Series. [The SAS] it contains the water
table and water within it is under mainly unconfined conditions; [however,] but beds of low permeability
may cause semi-confined or locally confined conditions to prevail in its deeper parts. The lower limit of
the [SAS] surficial aquifer system coincides with the top of laterally extensive and vertically persistent
beds of much lower permeability."8
intermediate aquifer system or the intermediate confining unit: "- includes all rocks that lie between
and collectively retard the exchange of water between the overlying [SAS] sufficial aquifer system [(or
land surface)]9 and the underlying [FAS] Floridan aquifer system. These rocks in general consist of
[coarse to] fine grained [silici]clastic deposits interlayered with carbonate strata belonging to all-er parts
of the [Oligocene] Miceene1 and younger S[s]eries. [Section omitted.11] The aquifers within this system
contain water under [semi-confined to] confined conditions. The top of the intermediate aquifer system
or the intermediate confining unit [IAS/ICU] coincides with the base of the [SAS] surficial aquifer system
[and on a local scale with land surface]. The base of the [IAS/ICU] intermediate aquifer is at [is
hydraulically separated to a significant degree from] the top of the [FAS]12 vertically persistent permeable
carbonate section that comprises the Floridan aquifer system, or, in other words, that place in the section
where plastic layers of significant thickness and permeable carbonate rocks are dominant. [Section
omitted.1]."
Floridan aquifer system: "- [a] thick [predominantly] carbonate sequence [that] which includes all or
part of the Paleocene to early [Lower] Miocene Series and functions regionally as a water-yielding
hydraulic unit. Where overlain by [the IAS/ICU] either the intermediate aquifer system or the
intermediate confining unit, the [FAS] Floridan contains water under confined conditions. When overlain
directly by the [SAS] surficial aquifer system, the [FAS] may or may not contain water under confined
conditions depending on the extent of low permeability material [within the base of] hi the [SAS] suffieial
aquifer system. Where the carbonate rocks crop out [or are covered by a veneer of siliciclastics], the
[FAS] Floridan generally contains water under unconfined conditions near the top of the aquifer system,
but because of vertical variations in permeability, deeper zones may contain water under confined
conditions. The [FAS] Florida aquifer system is present throughout the State and is the deepest part of
the active groundwater flow system on mainland Florida. The top of the [FAS] aquifer system generally
Although aquifer systems are based on hydraulic properties, correspondence with age does exist; "upper" is deleted
to allow more flexibility with regard to this correlation.
8 Second paragraph describing SAS in Southeastern Geological Society (1986) is omitted.
9 For example, the Peace River Formation is locally exposed at land surface in Polk County.
10 Now recognized as Late Oligocene based on the work of Scott et al. (1994).
" Related nomenclatural issues pertaining to the IAS/ICU are being addressed by the CFHUD II.
12 The lower extent of the IAS/ICU in the present study is also based on the relative degree of hydraulic separation
from the FAS.
13 Related nomenclatural issues pertaining to the IAS/ICU are being addressed by the CFHUD II.
FLORIDA GEOLOGICAL SURVEY
Gulf
of
Mexico
Geologic Map
0 5 10 20 30 40
i i Miles
0 5 10 20 30 Kilometers
Scale 1:1,750,000
Projection: Custom FDEP Albers
TQd.: : ',', -,','Q
Explanation sh~ --
Study Area .
Water Management Districts p', c
Stratigraphic Units h Qu
Qbd Beach Ridge and Dune
Qh Holocene Sediments Qh.a a
m Qu Undifferentiated Sediments .Qsu
STQd Dunes
TQsu Shelly Pho-Pleistocene Sediments Qu
rlTQu Undifferentiated Sediments TQd Q
TQuc Reworked Cypresshead Sediments Qh
Tap Avon Park Formation Tsu Qu
Tc Cypresshead Formation
Th Hawthorn Group (undifferentiated) .. '
Tha Hawthorn Group, Arcadia Formation Qh'. ...
That Hawthorn Group, Arcadia Formation, Tampa Member h .Tsu
The Hawthorn Group, Coosawhatchie Formation
Thp Hawthorn Group, Peace River Formation Qh Qh .
Thpb Hawthorn Group, Peace River Formation, Bone Valley Member
To Ocala Limestone
Ts Suwannee Limestone
Tt Tamiami Formation, ,
Figure 2. Geologic map of study area (from Scott et al., 2001) depicting the uppermost mappable
units within 20 ft (6.1 m) of land surface.
FLORIDA GEOLOGICAL SURVEY
The LFA lies beneath MFCU strata and
consists of the lower part of the Avon Park
Formation, the Oldsmar Formation and the
upper part of the Cedar Keys Formation (Miller,
1997). The Cedar Keys Formation forms the
lower boundary of the LFA and generally
consists of persistently dolomitized carbonates
with widespread bedded and intergranular
gypsum and anhydrite. Except for the
northeastern part of the study area, the LFA is
commonly highly saline and not used as a
potable or an economically treatable water
source. Research on use of the LFA as a
sustainable fresh water resource for the
northeastern part of the District is underway
(Southwest Florida Water Management District,
2006a).
The LFA is the lowermost known and well-
defined aquifer, ranging in elevation from -400
ft (-122 m) MSL in the northeastern part of the
study area to more than -2500 ft (-762.0 m)
MSL in Sarasota and Charlotte counties; LFA
thicknesses exceed 2,400 ft (731.5 m) in the
southeast part of the study area (Miller, 1986).
Per findings of the CFHUD II (Copeland et al.,
in review) the low-transmissivity strata lying at
the base of the FAS (e.g., the "sub-Floridan
confining unit" referenced in Southeastern
Geological Society, 1986) is informally referred
to as "undifferentiated aquifer systems."
Hydraulic properties of the FAS are
summarized in Figures 33-38 for the parameters
transmissivity, storativity, leakance, Kh, and
total porosity, respectively. A large degree of
vertical anisotropy exists in the FAS (e.g., Ryder
et al., 1980; Ryder, 1982) due to variations in
grain size and diagenetic factors affecting
permeability (e.g., Budd, 2002; Budd and
Vacher, 2004). Median horizontal and vertical
hydraulic conductivity values differ by three
orders of magnitude, which is notably less than
the difference between these same parameters in
the SAS and IAS/ICU. This is due in part to a
relative lack of sampling bias in the analyzed
FAS core samples. A greater degree of
anisotropy in the SAS and IAS/ICU relative to
the FAS is another possible contributing factor.
Anomalously high transmissivity values (Figure
33) likely reflect the influence of dual-porosity
(i.e. fracture/conduit flow). It is also noteworthy
that spatial analysis of dolines (e.g., sinkholes)
in the northern and central region indicates a
statistically significant correlation between FAS
hydraulic conductivity and doline-area ratios
(Armstrong et al., 2003).
Summary for UFA T (ft^2/day)
A nderson-Darling Normality Test
A-Squared 18.49
P-Value < 0.005
Mean 88602
StDev 187201
Variance 35044192303
Skewness 4.4198
Kurtosis 21.3092
N 90
M inim um 1300
0 200000 400000 600000 800000 1000000 1200000 1st Quartile 18650
S Median 38369
3rd Q uartile 69789
-- Maximum 1203210
95% Confidence Interval for Mean
49393 127810
95% Confidence Intervals 95% Confidence Interval for Median
n- I 29279 48540
Mean- I I 95% Confidence Interval for StDev
Median- 163279 219401
20000 40000 60000 80000 100000 120000 140000
Figure 33. Statistical summary of UFA transmissivity data from Southwest Florida Water
Management District (2006b). Asterisks in the box plot denote statistical outliers.
82030'W 82W
I I
81 30'W 81 W
I I
SCross Section
Locations
ALACHUA
I PUTNAM Miles
0 5 10 20 30 40
J.* / ":,,,Kilometers
S0 A' Scale 1:1,000,000
0 18 A Projection: Custom FDEP Albers
Do I MARION
Plate 5 15o075 B '
S6903 8883
B
CITRUS D' VOLUSIA
Plate 7 16611 16022 D' LAKESEMINOLE
M O e x ic o 15685 14917 SUMTER
S HERNANDO 1-1 16794 ,
Plate 8 E 1561 45 r | z
Z 1487r 3 1681 420 _Plate34 - s .N
- HEE I ORANGE
Plate 9 F 70Ex6plna16304tionF
13 1 1 Q W120 L, I
Plate 10 G 14046170564735.1 250165012 50124
14675 5863 15650 1606 116 6 5892
Z PASCO Plate 20 15601 5940 -
-IH Z' AA' N50120
lae 16609 13923 14669662 OSCEOLA
CC^ _DD2 14889H'
Plate 31 BB 775 C0 Pate3 14389
r Plate 1 12943 Plate 32
Z HILLSBOROUGH POLK -o
414668 R I
R I -I
*lt4K CunBBgs6 1 K6 14385 1M87
-,,
SPlate 14 5 642 14386 3852
ate36Plate 37 LA L _
BB' 500 03 0 ,= ,8,= 1 .
Q Plate15 GG HH DD' 9 o9 905 0
z C MANDATEE Ml .. OKEECHOBEE I
I- 0 8 HARDEE 681 -
M 7057 50098 16784 7 u 657 13514 15648 74
J Plate 16 ,l f 17 HIGHLANDS
15166 16303 \ Plate25 - V '
14882 16783 50100 W47 54
S \14872 Plate 26 1 DESOTO 44
Plate 17 SARASOTA 14383 DESOTO iI o1
Explanation 1- 1 714717 O W 5 314381 50105 w
0 15636 14787 17001
Study Area Plate18^ P' 106 102 18 17392 92864XZ
z Water Management Districts late288 I FF'
W ells GG' (315333 164 51 GLADES194
Plate 19 15683 1
CHARLOTTE
Core EE'
15289
S Cuttings % -
A Gamma Ray Log G c> 0LE HENDRY
83W 8230'W 82W 81 30'W 81 W
PLATE 1
NORTH Plate 32. Cross section: CC-CC' Hillsborough and Manatee Counties SOUTH
T27S T28S T28S T29S T29S T30S 30I T31S T31SI T3ES T3S I T33S
CC LAKE BOOT CSX RR CC
STARVATION LAKE CSX RR d
SLAK
CAR1Lw TTAMPA BAY
RAILROAD
W-50143 WRAP 2D TR 8-1
1 25 5 7W-16574 W-7672 W-15826
20
50 -
25-- 10
0 -- 0
- 25 - 10
FEET METERS
20
50
0 0
- 50
20
- 100
40
- 150
- 200 60
- 50
-80
-300 -
100
-350
-400 -- 120
-450 -
-140
- 500 -
-160
-550 -
-180
- 600
-650 -200
- 700
-220
-750
-240
- 800
- 850 - -260
-900 -
-280
-950
-300
-1000
-1050 -320
NO SPL UDSC
C,P,p,Q
C,P,p,L
-ARCADIA FM,
Nt
ARCADIA
FORMATION
AVON PARK
FORMATION
HORIZONTAL SCALE
MILES
0 1 2 3 4 5
0 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGGERATION IS APPROXIMATELY
126 TIMES HORIZONTAL SCALE
M,Ch
M,R
M,R,S
NO SPL
M.R,CS
M,R,Ch,S
M,R
M,R,I
M,R,S
M,R,S
M,R
M,R
M,R
M,R,D,Ch
NO SPL
L,R,S
NO SPL
NO SPL
L,S,Q
L
L,S,I,p
M,Ch,I,0,S
M,S,p
M,S,p,0
MSo.p
OCALA
LIMESTONE
(SEE TEXT FIGURE 9 FOR EXPLANATION
OF HATCH PATTERNS)
T.D. = -126
20
50 -
25- 10
- 25 -MT
FEET METERS
0 50 100
GAMMA (CPS)
SUWANNEE
LIMESTONE
20
0 50 100 50 -
GAMMA CCPS)
Sh 0 - 0
p.,T 50 -
--40
C,P,D,L
DT,
C 1 - 200 -
250 -
DR
f -140
pCD 150 -
:,P,D,L
S-200 60
S 400 -0
R 450-
,Sh-140
.MC 3500 -
,p --160
, -350 -
2.Mp. 400 - -0
- 650 -
M 700 -
".C
800-
aPy -160
S- 850 -60
-120
0 r 600-
R -650 20
700 300
0R -220
-1000
-240
0,D0 00 -
0R -85 - -s60
0 .M,
S- 900 -
09 -20 0
-1000 -
.---- -1050 - -320
0' BLS
AVON PARK
FORMATION
82030'W 82W
Peace
0 5 10
River Formation
Surface
20 30
Miles
,z Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 25 ft
Projection: Custom FDEP Albers
I
Gulf
of
Mexico
es0
Explanation N
SStudy Area
o Wells Used
Contours
z~ - Peace River Fm. Extents
- Water Management Districts
Peace River Fm. Surface (ft. MSL)
>125
-35
<-200
--f
I
I
o
SS o
S o
o
-^^ 0
-^ 0
o 0 a
--I
~1
00 0 0
o o
o- 0 0f
PLATE 51
I
83W
81
o
ul
0 0
0, 0
FLORIDA GEOLOGICAL SURVEY
Structural Features
0 5 10 20 30 40
- -Miles
0 5 10 20 30 40
Kilometers
Scale 1:1,750,000
Projection: Custom FDEP Albers
Explanation U '- /__
Study Area FG-2
S Fault Groups
Plunging anticline "
4, Plunging syncline 4
Proposed Faults
- Present Study (inferred) -
--Sproul et al., 1972
---Winston, 1996
--Hutchinson, 1991 B Okeec obee
==== Christenson, 1990 Ba n
--- Miller, 1986 __
--Pride et al., 1966
---Carr and Alverson, 1959
--Vernon, 1951 C
Figure 3. Structural features within the study area. A Florida Lineament; B pre-middle
Jurassic plunging syncline inferred from Barnett's (1975) "sub-Zuni" map; C "Broward
Syncline;" D Ocala Platform; E Kissimmee Faulted Flexure; FG-1 fault group along strike
with fault inferred in present study; FG-2 group of reported faults possibly affecting subcrop
extent of the Ocala Limestone. U/D upthrown/downthrown block.
Gulf
of
Mexico
Plate 30.
T16SIT17S
Cross section:
T17S TIeS
AA AA'
TIS TIT195S
Marion, Sumter, Hernando, and Pasco Counties
T19S IT2OS
T20S T2IS
T21S1T22S
T2=S T23S
csx @ a 0
QUARRY
0 9
PRINCESS
LAKE
OUTLET
RIVER
ROMP 119 ROMP 112 ROMP 110 W-15942 ROMP 99
W-15643 W-16617 W-16611 W-16304
MR OCALA
.R LIMESTONE
M.R
M,R
s AVON PARK
SURFIIAL S SAND C CLAY
-140GRAVEL FINE MEDIUM COARSE
.F-DOLOSTONE. AQUIFER SYSTEM/
CONFINING UNIT
SAND FINE MEDIUM COARSE AOUIFER
-- INTERBEDDED UMESTONE AND DOLOSTONE
SILT FINE MEDIUM COARSE
PHOSPHATE GRAVEL
PHOSPHATE SAND
ORGANIC
SPAR
IRON STAIN N
QUARTZ
ANHYDRITE
CHERT
0 50 100
GAMMA (CPS)
CCh UDSC
MT
Vc OCALA
s. LIMESTONE
MCD.0
M,.,D'
M.S.C.OD
M.S,O.D
MRS.D
M.R.S.OD
RM.S
M,R,S.D
pO SPL
D,.Ch
D
M,D,.C
M.D.O Ch
M DCh Q
M.S.D.Ch
Dh
DCh
D.M.Ch
D.O
M,DO.S,Q
NW
M.D
MD, Ch,C,0
M,D,Ch,S
M.D.Ch
MD
M.D.CPyF
D,Q.O
M.D.OO.Ch
AVON PARK
FORMATION
SHELL
DOLOSTONE
UMESTONE
HEAVY MINERALS
NO SAMPLE
PYRITE
SEMI-CONFINED TO UNCONFINED
FLORIDAN AQUIFER SYSTEM
S m10m 20
C MA (CPS)
UDSC
MR OCALA
R OCALA
; LIMESTOI
M.0
0.P
AVON P
NO SPL FORMAT
NO SPL
T,C
c.o.Py
0h h
RCh
0,R
R
Ry
NE -
ARK
ION
0 50 100
GAMMA (CPS)
-aR -^
0 c
0.M
0
0
R
D
0.M
h,QG0
GICh.Q.0
0,R,G
|.C.Py
G.O.R
AVON PARK
FORMATION
HORIZONTAL SCALE
MILES
0 0,5 1 2 3 4 5
00.5 1 2 3 4 5 6 7 0
KILOMETERS
SVERTCAL EAERATION IS APPROXIMATELY
108 TIMES HORIZONTAL SCALE
wLA CHEW SHEL BE
GYPSUM
SS~T
tIP
NORTH
4AA
T13SlT14S
T14S IT15S
T15SIT16S
- 25 -
FEET METERS
200 6 o
W-892
TD = 400' BLS
-200 - 60
THLOOCHEE
RIVER
JUMPER
CREEK
T23S T24S5
T24S |25S
SOUTH
AA'
T25S T26SS
- 400 -
-450
HAWTHORN
- 50 -200
MMA 150 200(CPS)
GAMMA (CPS)
W-662
FEET METERS
200 60
TAMPA MEMBER
OCALA
LIMESTONE
AVON PARK
FORMATION
NOT AVAILABLE
o -I-
-200 -h
OCALA
LIMESTONE
AVON PARK
FORMATION ?
-400 -120
- -200
--t2mmMmEr-41
tEE NN I I -
Ea=
60
150
C I.
-120 M I
-500
-2no
-22.0
- SaO --
- 800 -
Plate 27. Cross section: X-X' Sarasota, DeSoto, Highlands, and Glades Counties
R22E1R23E R22E1R23E R24EIR25E RE6E0R27E R27E1R62E R28E|R29E R29EIR30E R30E R31E
200 60 mCSX'RR ""m
50 1 50 w
4040
no 100 303
50 00 50
10
-10 1
T ROMP 9 W-1691 VW50106 W-50102 ROMP 12 ROMP 13 W-50104 VW-9286 W-15880 U S
W-17056 W-16578 W-17392 GAMMAO CPS)
10020
50 -- 0C GAMA (CPS) L SCALE AVA.qILA LE G PS ,L D0 0
N,, CSICpC,L,JCh
-- -- --c. oS r--..
c-MpPEACE .- MCT CCTP pa--0
- so ,00RIVER- UDSS .Rp c.
- --o 0M FM. NO SPL PEpL -.- 20
-LPEACMppSM P- ECE RIVER -
-40 C M40P
- 500 -pCDDM-
ou P TAMPA -050*.c p .Mp,
so MBR. - -* OPL t
N O S P L 14. pM ,CE p l M ,R.
2O pPFM NpSh M,R OS
'P':: PIS M'p MSB
_ a -z o 0 c s O M.N s -0 o - o
c, 'A, ,p.PACEA-PRCAA IVIAER
ORMM.D~phFRAIATION ,Np- -050
MsP N,,COp AC A . M
- 300 -P-0-..,-Np 00
HMRpN,pC MRp
0 -100 ',S .CN p SP RpS --100
C .P.p.M .. to,
L -Jo -,NCATE hR FFMp
-060C-:PN:P0c
PI, mM .NCpSP
-550 -5 40
-600 0 --pM:- 00
-650UV NEE* D MRCDp
-700 MppM R-7 -
0 P- 220
-150 -75..0' NOATE
-BR NO SPMPR, -lP,
-24 OCALA -2-0
8 M MLIMSTON
- -0 --0
-900 -90 0
-20 GoP D P M R, -Bo
FM,5"--"-260 LR 5 0
-5 7R3 M ('I ML
-3..0 0 -M,R 3---,--0 0-
S :PIS MC'D DHSR
ARCADIALPRAR
-00 MM M TI- -00
LI NE r NaR,3sh AVON
R - FORMATION -40 -
300 / -000
-340 -R4,L0C
-usD- s -- ...-100
Well -f. 0s503 HORIZONTAL SCALE -3-00
MILES (SEE TEXT FIGURE 9 FOR EXPLANATION
S AVON PAR 1 2 3 4 5 OF HATCH PATTERNS) ...- .
FORMATION 0 2 4 6 8 -_
i SPL KILOMETERS
- 400 ] I-
BULLETIN NO. 68
CROSS SECTIONS EXPLANATION
HATCH PATTERNS
LIMESTONE-
FINE MEDIUM COARSE
t ---DOLOSTONE
FINE MEDIUM COARSE
INTERBEDDED
LIMESTONE & DOLOSTONE
FN MEIU COA
FINE MEDIUM COARSE
CLAY
SURFICIAL
AQUIFER
SYSTEM
INTERMEDIATE
AQUIFER SYSTEM /
CONFINING UNIT
FLORIDAN
AQUIFER
SYSTEM
MID-FLORIDAN
CONFINING UNIT
AAAAAAAAAAA
hA LA AAA A A
IAA A LAAAA haAl
AAAAAAAAAAI
AAAAAAAAAAA
CHERT
COMMENTS
M MICRITE
S SAND
P PHOSPHATE GRAVEL
D PHOSPHATE SAND
O ORGANIC
R SPAR
I IRON STAIN
Q QUARTZ
A ANHYDRITE
Ch CHERT
T SILT
C CLAY
Sh SHELL
D DOLOSTONE
L HEAVY MINERALS
No Spl NO SAMPLE
G GYPSUM
Py PYRITE
S THIN MANTLE OF IAS/ICU SEDIMENTS
' SEMI-CONFINED TO UNCONFINED
FLORIDAN AQUIFER SYSTEM
* CUTTINGS EXAMINED IN THIS INTERVAL
INDICATE FORMATION PICKS SHOWN
Figure 9. Explanation (legend for cross sections).
GRAVEL
SAND
+ +++
SHELL BED GYPSUM
t
FLORIDA GEOLOGICAL SURVEY
An assessment of the flow of variable-salinity ground water in the middle confining unit of
Floridan aquifer system, west-central Florida: U.S. Geological Survey Water-Resources
Investigations Report 89-4142, 13 p.
Hine, A.C., 1997, Chapter 11-Structural and paleoceanographic evolution of the Florida Platform, in
Randazzo, A.F. and Jones, D.D., eds., The Geology of Florida: Gainesville, University Press of
Florida, p. 169-194.
Hine, A.C., Suthard, B., Locker, S.D., Cunningham, K.J., Duncan, D.S., Evans, M.W., and Morton, R.A.,
Karst subbasins and their relationship to transport of Tertiary siliciclastic sediments on the
Florida platform, in Swart, P., Eberli, G., McKenzie, J., eds., Perspectives in Sedimentary
Geology: A Tribute to the Career of Robert Nathan Ginsburg: International Association of
Sedimentologists Special Publication 41: Oxford, UK, Blackwell Publishing, (in press).
Huddlestun, P.F., 1988, A revision of lithostratigraphic units of the coastal plain of Georgia The
Miocene through Holocene: Georgia Geological Survey Bulletin 104, 162 p.
Revision of the lithostratigraphic units of the coastal plain of Georgia the Oligocene: Georgia
Geologic Survey Bulletin 105, 152 p.
Hutchinson, C.B., 1992, Assessment of hydrogeologic conditions with emphasis on water quality and
wastewater injection, southwest Sarasota and west Charlotte Counties, Florida: U.S. Geological
Survey Water-Supply Paper 2371, 74 p.
Johnson, R.A., 1986, Shallow stratigraphic core tests on file at the Florida Geological Survey: Florida
Geological Survey Information Circular 103, 431 p.
Johnston, K., Ver Hoef, J.M., Krivoruchko, K., and Lucas, N., 2001, Using ArcGis Geostatistical
Analyst: Redlands, ESRI Incorporated, 300 p.
Johnston, R.H., and Bush, P.W., 1988, Summary of the hydrology of the Floridan Aquifer system in
Florida and in parts of Georgia, South Carolina and Alabama: U.S. Geological Survey
Professional Paper 1403-A, 24 p.
Jones, I.C., Vacher, H.L., and Budd, D.A., 1993, Transport of calcium, magnesium and SO4 in the
Floridan aquifer, west-central Florida: Implications to cementation rates: Journal of Hydrology, v.
143, p. 455-480.
Jones, G.W., Upchurch, S.B., Champion, K.M., and Dewitt, D.J., 1997, Water-quality and hydrology of
the Homosassa, Chassahowitzka, Weeki Wachee and Aripeka spring complexes, Citrus and
Hernando Counties, Florida -Origin of increasing nitrate Concentrations: Brooksville, Southwest
Florida Water Management District, Ambient Groundwater Quality Monitoring Program, 167 p.
Jones, G.W., Upchurch, S.B., and Champion, K.M., 1998, Origin of nutrients in groundwater discharging
from the King's Bay springs: Brooksville, Southwest Florida Water Management District,
Ambient Groundwater Monitoring Program, 159 p.
Jorgensen, D. G., Helgeson, J. 0., and Imes, J. L., 1993, Aquifer systems underlying Kansas, Nebraska,
and parts of Arkansas, Colorado, Missouri, New Mexico, Oklahoma, South Dakota, Texas, and
Wyoming--Geohydrologic framework: U.S. Geological Survey, Professional Paper 1414-B, 238
p.
Plate 15:
Cross section: L-L' Manatee, Hillsborough and Polk Counties
RISE R19E R19E R20E
150 40
100 - 30
20
50 -
10
0 0
-10
- 50
FEET METERS
150 45
[- 40
0 25 50 75
GAMMA (CPS) 25
50 75 100
UDSC
ARCADIA
FORMATION
100 -
50 -
0
- 50 -
- 100 -
- 150 -
-a -
- 200 -
-250 -
- 300 -
-350 -
-400 -
-450 -
- 500 -
--45
-550 -
- 600 -
-650 -
- 700 -
-750
- 800
OCALA
LIMESTONE
4 5
6 7 8
AVON PARK
FORMATION
o
T)=-1695 BL$
gggg
I :-*:-*: *
;;~~~ Sijj^
*** *-*
5 I1I1I1I1I1I1IT
I I I I 'i'i'i'i'i'i'
TD = -1695 BLS
R20E R21E SOUTH FORK R21E I R22E
S LITTLE MANATEE
OLD RR GRADE RIVER 0
NORTH FORK
MANATEE RIVER c
39
6740
IMPERIAL LAKES HELLER ROMP
W-50095 W-50097 V-16
EAST
L'
R22E JR23E
ROMP 40
/ W-50003
150 -i 40
o100 - 30
20
50 -
10
10
- 50
FEET METERS
0 125 250
GAMMA (API) U
D,I UDSC .-
c p PEACE RIVER -
FORMATION
ARCADIARCAFIA
pD FORMATION
MC E- -
Cp
9F 1
P, C ARCADIA
p,D
pR TAMPA MEMBER K
,ARCO FORMATION
LCM
DCh,M P
CpM
M,D
M,C,D T MEMBER
,M O
C:D:PM {OCALA |
1,), FORMATION
M:SCTisfS^^s~a^
M j C^ ,H H,,
-1-
I
i
I.
(SEE TEXT FIGURE 9 FOR EXPLANATION
OF HATCH PATTERNS)
T.D. = -1260' BLS
WEST
TR 8-1
W-15826
- 20
SUWANNEE
LIMESTONE
-850 --260
- 900-
-950-
-1000 -
- -300
-1050 -- -320
-1050 -L -320
-
0 150 300
S 150 -
a L GAMMA (CPS)
N SPL -1
Sp
50-
PC.D
C,D 0 -
C,p
S- 50 -
L,D,p
C
C,D 100
i--
D SPL
150 -
M
;,D
D 200
L
DC
D 3
S-250-
C hD -
L D
D
MD 300 -
D
-350 -
D
D
400 -
D,Ch
D.C
- 500
-D 550 -
600 -
D
700 -
-750 -
S- 900 -
-50 -
0-900
L
-1000 -
- 260
- 60
- -120
- -140
- -160
- -180
- -200
82030'W 82W
0 5
Nocatee Member
of the Arcadia
Formation Surface
10 20 30 4
Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour interval: 75 ft
Projection: Custom FDEP Albers
Gulf
of
Mexico
- f- -
Explanation (
m Study Area
Wells Used
Contours
Nocatee Mbr. Extents
z- - Nocatee Mbr. Extents
- Water Management Districts
Nocatee Mbr. Surface (ft. MSL)
>0
-300
<-600
PLATE 47
Miles
I
I
S
I--
I
--I
~1
0 -.
83W
81 OW
I
WEST
G R16E IR17E
Plate 10. Cross section: G G' Pasco, Sumter and Polk Counties
R17E R18E
R18E R19E
R19E R20E
R20E R21E
R21E I R22E
BROOKSVILLE RIDGE
@
- 80
- 60
- 40
- 20
- 0
R22E R23E
GREEN SWAMP
EAST
R23E R24E G'
C,
TR 17-3
W-14675
GAMMA LOG
NO SCALE AVAILABLE
W-14046
p
Sh
C.I.Sh ,
OS SP
M.R S
m
m
m
M.R
M.R
0
M.R
M.R
M
M
MD
M
M.R
M.R.O i
M.D
NO SP
M.D
M
0
150 -
100 -
50-
0-
- 50-
-100 -
-150 -
-200-
-250-
-300-
-350-
-400-
-450-
5
-500-
-550-
-600-
- 40
- 20
-L 20
FEET METERS
W-5863
ROMP 93
W-14336
0 100 200
GAMMA (CPS)
?C UDSC
M.RCFI LIMESTONE
M.R
-M OCALA
M.R LIMESTONE
0
SAVON PARK
FORMATION
NO SPLr
NOTE
THIN
OF A
OF I
PRESE
ROMP 90
W-15647
c
c UDSC
CJE
S SUWANNEE
M.R LIMESTONE
M.R,S
M,Ch
M.R
R
M,R OCALA -
LIMESTONE
MR
M.R
M.R
M,R
M
NO SPL
Ch
M
M AVON PARK
MD FORMATION
M.D
M D
M,D
M.D
) BED OF
BER
N
LU
ROMP 89
W-5054
0 400
0 50 100 L I1
I I I GAMMA (CPS)
GAMMA (CPS) UDSC_
""UDSC ..- -
ns, OCALA
M.o LIMESTONE
M
,Ch PL
M.R.C.Il
M.R
M.RD
M.R
M.D
M.O.Ch
0.
M.R
M.R
M.D AVON PARK
M.R FORMATION
M.D.R.O
M.R.D _
D
S0
M.D.R.O
NO SPL
M2
M.D.O
L
1.0
S
S
C.T
S
L.O.Py
S.p?
S.o
0
Q0
Q..
UDSC
| | | | | *
1 1 1 1 ~~t
I I I 1*LTJ
' ' '
1 1 1 1 1 *
Simn
n m 3
'Smn
ROMP 88
W-15650
0 50 100
I I I
GAMMA (CPS)
C.I.Ch
M.C.S.Ch
M h
M.Ch,
M
M.C
M.p.C.Py,R
M.Py.Sh
M.D
M.D
M.Ch.I
O SPL
M.R
M.R
M.RT,0 O
M.D
M
:
(LESS THAN 10)
SIBLE TAMPA MEM
ARCADIA FORMATIO
HAWTHORN GROUP
SENT IN THIS WEL
__- -- DOLOSTONE .
SAND FINE MEDIUM COARSE
-- INTERBEDDED UMESIONE AND DOLOSIONE--
SILT FINE MEDIUM COARSE
CLAY CHERT SHELL BED GYPSUM
HORIZONTAL SCALE
SSURFICIAL
AQUIFER
SYSTEM
FLORIDAN
SYSTEM
MICRITE T
SAND C
PHOSPHATE GRAVEL Sh
PHOSPHATE SAND D
ORGANIC L
SPAR H
IRON STAIN NO SPL
QUARTZ G
ANHYDRITE Py
CHERT
SILT
CLAY
SHELL
DOLOSTONE
LIMESTONE
HEAVY MINERALS
NO SAMPLE
GYPSUM
PYRTIE
0 1 2 3 4 5
0 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGGERATION B APPROXIMATELY
165 TIMES HORIZONTAL SCALE J
C,H I
MR
M,R
M
M.R
M SUWANNEE
LIMESTONE
M
M
M
M
M
M OCALA
m LIMESTONE
M
M
M R
M.R D
M:RgD
M.R
M.R.Py
AVON PARK
FORMATION
SE
** DENOTES LOG SHIFT BACK TO BASEUNE
EXPLANATION
HATCHING PATTERNS
LIMESTONE
FINE MEDIUM COAR
- 20
FEET METERS
150 -
40
100 -
20
50
0 -I-
- 50-
-100 -
-150 -
-200 --- o60
- -160
- -180
-650 -L -200
GRAVEL
-250-
-400 --- -120
- 650 -L -200
Iamvm=
MTmm=
&=Tmmw
BULLETIN NO. 68
general, the younger formations follow this
pattern, however, many are not observed
throughout the full extent of the study area (i.e.,
absence of the Peace River Formation
[Hawthorn Group] in the northern third of the
District). In the sections that follow, details of
the features and processes affecting the overall
geologic framework are discussed.
Structure
Numerous structural features affect the
thickness and extent of geologic units in the
study area (Figure 3). The oldest known
"basement" feature in the region is the Bahamas
Fracture Zone (Klitgord et al., 1983), which is
also referred to as the Jay Fault (Pindell, 1985).
This zone bisects the Florida peninsula basement
from Tampa Bay southeast to the Lake Worth
area on the east coast. Lithologic and
geophysical data suggest that this basement
feature represents an Early Mesozoic transform
fault that was important to the development of
the Gulf of Mexico. Christenson (1990),
however, suggests that based on assessment of
more recently acquired borehole geology and
magnetic anomaly data, the feature represents a
Triassic-Jurassic extensional rift margin with
little to no lateral offset. He proposes the name
"Florida Lineament" to describe this feature,
which coincides with the Jay Fault and the
Bahamas Fracture Zone across peninsular
Florida (Christenson, 1990; see feature "A" in
Figure 3).
The South Florida Basin (Applin and Applin,
1965; Winston, 1971) is a stratigraphic basin
that contributed to southward thickening of
Mesozoic and Early Cenozoic lithostratigraphic
units in the southern Florida peninsula (Figure
3). A possible successor basin, the younger
Okeechobee Basin (Riggs, 1979a) may have
contributed to south southeastward dipping of
Oligocene and older lithostratigraphic units
along the eastern margin of the study area
(Highlands and Glades Counties).
The influence of "basement" structures on
Cenozoic and younger stratigraphic units is
poorly understood. For example, an apparent
southeast plunging syncline ("B" in Figure 3)
trends from Sarasota to Hendry Counties in the
"sub-Zuni" (i.e., pre-Middle Jurassic) map
presented in Barnett (1975). Shallower
northwest-striking faults reported by Winston
(1996) occur in the same region. Maps of the
structural surface of Eocene rocks (Miller, 1986)
indicate a generally south-plunging trough
extending from central Charlotte County.
Deepening and thickening of units in the
Charlotte County region are observed in the
present study (see Il lthmiting, ,lhy, p. 30). The
Early Cretaceous "Broward Syncline" (Applin
and Appin, 1965; "C" in Figure 3) is located
approximately 20 mi (32 km) to the east of
feature "B" and has a generally parallel strike.
These inferred faults and basement relationships
warrant further study, especially given their
potential role in water quality and distribution of
permeable zones. Knowledge of the distribution
of low-permeability sediments beneath the FAS
is also important as potential sites for CO2
sequestration are explored.
The Ocala Platform ("D" in Figure 3) is the
most dominant feature in the central peninsular
region. Evidence of this platform is apparent in
the geologic map (Figure 2) where the Eocene
Avon Park Formation (Tap) and Ocala
Limestone (To) are exposed at or near land
surface. This feature is also evident in the
Environmental Geology composite map (Figure
4), which reflects lithologic and sediment types
within 10 ft (3.1 m) of land surface. Shallow or
exposed carbonate rocks in Levy, Marion, Citrus
and Sumter Counties reflect the influence of the
platform. This structure is not thought to be an
uplift (Winston, 1976) but rather a tectonically
stable area on which disconformable marine
sedimentation and differential subsidence has
occurred (Scott, 2001). It is also a major
controlling factor in the thickness and extent of
lithostratigraphic units in central and
southwestern Florida. As a result, this feature
also has a very significant effect on the
distribution of regional aquifer systems.
Remaining structural features are discussed
in this section from north to south. Several
northwest-trending faults, as well as orthogonal
fracture traces (or lineaments), have been
proposed within the Levy and Citrus County
area by Vernon (1951). It is possible that some
WEST Plate 28. Cross section: Y-Y' Charlotte and Glades Counties EAST
y R22E IR23E R23EIR24E R24EIR25E R26EIR27E T40S T41S R27E R28E Y
20 60 PEACE RIVER 41 RAILROAD O 60
50 ALLIGATOR BAY 50
150- LEVES 1 31 150
CR EK PORT 6 PEACE SHELL 540
1 30 CHA OTTE RIVER CREEK 100 30
00 5 0
- 10 10
-50 -50 -
TR 2-1 V-16134 W-50103 *ROMP 5 W-9200 V-16944
FEET METERS W-15333 W-16913 FEET METERS
- I o 5 s0
50 0 50 T GAMMA (CPS GAMMACPS) 50 -
S GAMMACCPS )KGAMMA (CPS) GAMMA (C CPS) LSh L TC Mp 0
o o UDSS MSCs UDSS UDSS \ M '
-3- NP;. PEACE RIVERp Cp.P.J -
:- I s FORMATION . .
P-1DTT0 P E A C E R I V E R T
400T0H RC 100,-
C- - -ap- p- s - 0 - M0
.M MSpR : FORMATION "S 'pCT
-10 0 x -I i 60
15 S0 Lp 50
....A..p.. M,LRTD
S5 -ARCADIA eLpSMpR, -
-3 C 1 T ,,M -ATION
l R C A DIAsR L N O C A T E E MpAR C A D IA _-
-- IC FORMATFORMATION PICBS SMT1 1
- ,P- -i cTp- M: S,PR 1 -40
-4oo -C4o L.D.S J L I I 1 - -- ..: _- M,Ro -
-E50---0 IMST N 2 ---
-1300 L * *MS-- 2 7 0 D
NOCATEE .c.0, Dp-140
16 --- H- -MERN Z ,L.S.L..1 1 n - -1o
- .R M.R ,Rp, -00
ARD,,L Lp,A
FORMATION ).C Lp MEMBER ,,p,$
-.5 -1000RL-,p a
-350 eKILOME-350 -C-R
F RAo Ms.c:. -opF A
- -oo- --S
400N-2EEOIOTLSCL UANE-4" -
_M TLIMESTONE
LSES NL.MS
- _1- -24: --- ---- -- ARD' ----40
--3 HRIZNTAL SCALE LUANE..- -
-1, C- -32,S0 -0050 --
-M -10 M--,C,- S, ---so ,-p /
-,oo MEMBER -160
-5 -5400MM -4R5 40-
00M'P FA8 OLMATIONE
-- If-1 -600
-600 TKZ7TRCD.R
PIP, (SEEOTEXTAFIGUREI9NFOREXPLANATION R
-5000 OFHAMTCHPATTERNS)-6500
-400 ND,.RR -340
BULLETIN NO. 68
Up to three relatively more permeable water-
yielding zones exist in the latter regions (Corral
and Wolansky, 1984; Trommer, 1993; Torres et
al., 2001; Knochenmus, 2006), which provide
groundwater to municipalities, industries and
agriculture. During 2000, the IAS/ICU was the
source of approximately 10 percent to 15 percent
of total groundwater withdrawals in DeSoto,
Hardee, and Highlands Counties (Marella 2004).
In Sarasota and Charlotte Counties, the usage
was 32 percent and 75 percent respectively
(Marella, 2004).
Lithology and hydrology of IAS/ICU
permeable zones is heterogeneous and complex.
Where multiple water-producing zones exist,
they are generally laterally discontinuous and
difficult to map, even with the aid of
hydrochemical assessment (Knochenmus and
Bowman, 1998; Knochenmus, 2006).
Moreover, the hydraulic character of the
IAS/ICU is unpredictable due to varying degrees
of vertical and lateral permeability within the
unit. In the northern region, IAS/ICU sediments
generally occur along upland features such as
the Brooksville Ridge, Fairfield Hills and
Sumter and Lake Uplands (Figure 6, Plate 56).
This hydrostratigraphic unit also occurs
throughout the central and southern regions.
Maximum IAS/ICU elevations exceed 125 ft
(38.1 m) MSL along the Brooksville and
Lakeland Ridges. Thickness of the IAS/ICU
ranges to more than 900 ft (274 m) in the
southernmost part of the study area (Plate 57).
Various extents of IAS/ICU water-producing
zones have been proposed within the study area
(Figure 23). In the Florida Aquifer
Vulnerability Assessment (FAVA), (Arthur et
al., in review) the extent includes Miller's
(1986) delineation plus a region defined by the
distribution of FDEP-regulated public water
supply wells that utilize the IAS/ICU (Figure
23). Included among the FDEP supply-well
region is a 12.4 mile (20 km) buffer, which was
added to account for lateral uncertainty (Arthur
et al., in review). In the present study, however,
lithologic data represented in cross sections were
assessed to re-define an approximate northern
limit of IAS/ICU permeable zones (Figure 23).
This redefined extent is comparable to that
proposed by Basso (2003). The region north of
the zone is dominated by variably low-
permeability IAS/ICU sediments, except for
localized relatively permeable sediments within
the Brooksville Ridge (e.g., W-15933; Plate 9).
Within the northeastern part of the study
area, the IAS/ICU is comprised of the
Coosawhatchie Formation (Hawthorn Group)
and possibly other Hawthorn Group units (i.e.,
the Marks Head and Penney Farms Formations)
(W-8883, Plate 5; W-12794, Plate 8). In the
central part of the northern region, the IAS/ICU
occurs along the axis of the Brooksville Ridge
and is comprised of undifferentiated Hawthorn
Group sediments (e.g., W-6903, Plate 5; W-
15933, Plate 9). Scott (1988) suggests that these
sediments at one time likely blanketed the entire
northern region. In the lowlands flanking the
Brooksville Ridge, laterally discontinuous
Hawthorn Group remnants (possibly reworked)
or Pliocene-Pleistocene clayey sediments (e.g.,
W-707, Plate 9) function hydrologically as semi-
confining sediments that promote local FAS
artesian and perched water-table conditions.
As indicated by the hachured areas in Plates
56 and 57, at least half of the northern region is
discontinuous with respect to semi-confining
sediments of the IAS/ICU. This qualitative
delineation is based on inspection of borehole
lithologic data, assessment of the state geologic
map (Scott et al., 2001) and topographic analysis
(i.e., comparing Hawthorn Group distribution
and depth to carbonate rocks with the 15 m (49.2
ft) resolution DEM. In some of these areas, the
IAS/ICU is absent and local aquifer conditions
range from SAS overlying FAS (with varying
degrees of hydraulic separation) to unconfined
FAS. Thickness of the IAS/ICU along the
Brooksville Ridge and the northeastern part of
the study area averages -35 ft (-11 m) and
locally exceeds 100 ft (30.5 m) (W-15933, Plate
9). Highly variable and localized IAS/ICU
thicknesses in these areas are due in part to
infilling ofpaleosinks. Plates 5 and 6 reflect this
scenario, however, due to the localized
occurrence, the IAS/ICU was not delineated.
In the central region, hydrogeologic
properties of the IAS/ICU are highly variable
due to lithologic heterogeneity and complex
interbedding typical of the Hawthorn Group
82030'W 82W
0 5
Arcadia Formation
Thickness
10 20 30 4
wKilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 25 ft
Projection: Custom FDEP Albers
Gulf
of
Mexico
- f,~
o-
0 o\ -
N. ., I ---1- t -----
S
S I ~~^
oy_ I^ I I
o o
o ; \ rL
n 0 _0 0
A
--I
-I
Explanation
I |J Study Area
o Wells Used
Contours
.- .- Arcadia Fm. Extents
- Water Management Districts
Arcadia Fm. Thickness (ft.)
>750
375
o-,50
hko
PLATE 46
Miles
I
I
83W
81 OW
I
0
- MA.
STATE OF FLORIDA
DEPARTMENT OF ENVIRONMENTAL PROTECTION
Michael W. Sole, Secretary
LAND AND RECREATION
Bob G. Ballard, Deputy Secretary
FLORIDA GEOLOGICAL SURVEY
Walter Schmidt, State Geologist and Director
BULLETIN NO. 68
HYDROGEOLOGIC FRAMEWORK OF THE SOUTHWEST FLORIDA
WATER MANAGEMENT DISTRICT
By
Jonathan D. Arthur, Cindy Fischler, Clint Kromhout,
James M. Clayton, G. Michael Kelley, Richard A. Lee, Li Li,
Mike O'Sullivan, Richard C. Green, and Christopher L. Werner
Published for the
FLORIDA GEOLOGICAL SURVEY
Tallahassee, Florida
in cooperation with the
SOUTHWEST FLORIDA WATER MANAGEMENT DISTRICT
2008
FLORIDA GEOLOGICAL SURVEY
Figure 16. Assemblage of typical Bone Valley Member fossils. Clockwise from upper left: ray
spines, shark vertebra, shark teeth, horse teeth, alligator tooth in matrix, (nickel for scale) dugong
rib, mammoth tooth and bone fragment. Background is a slab of Avon Park Formation dolostone
with Thalassodendron sp. carbonized impressions. (Photo credit: Jon Arthur, FDEP-FGS).
Limestone is locally absent (Plate 39).
Delineation of the Peace River Arcadia
Formation contact is problematic in some
localities. In many cores, the two units appear to
be conformable, with phosphate-rich
siliciclastics grading with depth to more
siliciclastic-interbedded carbonates containing
generally finer-grained and less abundant
phosphorite. Thickness of this transition zone
may exceed tens of feet. With increasing depth,
Arcadia Formation lithologies become more
dominant. In such cases, the lower contact of
the Peace River Formation is estimated based on
sedimentary structures as well as a best
approximation of where the overall lithologic
sequence becomes more carbonate dominant. In
contrast to the locally gradational contacts, other
areas provide strong evidence of an
unconformity, where a phosphatic rubble zone
occurs at the base of the Peace River Formation
(Scott, 1988).
Post-Pliocene/Miocene sediments disconformably
overlying the Peace River Formation in the
study area are comprised of fossiliferous sands,
clays and shell beds with variable amounts of
limestone and reworked phosphorite (e.g., Plate
11, W-14389 [ROMP 76] and Plate 13, W-
16576 [ROMP DV-1]). The contact of these
sediments with the Peace River Formation can
be difficult to determine because of lithologic
similarities (e.g., clays and phosphorite),
especially where the uppermost beds of the
Peace River Formation have been leached by
groundwater, giving the sediments an
appearance similar to that of some post-
Hawthorn Group lithologies. In addition, it can
be very difficult to distinguish Peace River
Formation sediments from those of reworked
Peace River sediments (e.g., post-Hawthorn
Group undifferentiated sands and clays) when
studying cores (the distinction is extremely
difficult to impossible when evaluating
cuttings).
FLORIDA GEOLOGICAL SURVEY
Suwannee Limestone (Figure 8).
Gamma-ray activity in the Arcadia
Formation is distinctive, with strong gamma-ray
peaks characterizing the upper undifferentiated
part of the unit (e.g., W-16784 [ROMP 33],
Plates 16 and 37; Figure 10). Lithostratigraphic
members within and below the formation are
characterized by significantly weaker gamma-
ray responses. For example, where the
undifferentiated Arcadia Formation overlies the
Suwannee Limestone, the gamma-ray response
for the older unit is often contrastingly low in
gamma-ray activity (e.g., W-15683 [TR 3-3],
Plate 19 and W-15333 [TR 2-1], Plates 19, 28
and 37). Although the high gamma-ray activity
sequence in the Arcadia Formation is distinctive,
it is not always useful as a diagnostic tool for
identifying the upper formational boundary.
Phosphate lag deposits locally comprising the
base of the Peace River Formation have gamma-
ray peaks as high as that of the Arcadia
Formation.
Deposition of the Arcadia Formation is
somewhat unique owing to its composition of
mixed carbonate and siliciclastic sediments. In
most depositional environments, an influx of
siliciclastic sediments usually inhibits the
production of carbonates. During the Oligocene,
siliciclastics began to deposit along the Florida
Platform (Hammes, 1992; Missimer, 2002).
This influx of siliciclastics, during low sea-level
stands, began to slowly bypass the Georgia
Channel System (Huddlestun, 1993) as it filled.
By Late Oligocene the lower part of the Arcadia
Formation was being deposited and a more
continuous influx of quartz sand was occurring
(Missimer and Ginsburg, 1998). These
siliciclastics were transported south several
hundred kilometers to the southern part of the
Florida carbonate platform by longshore currents
(Scott, 1988; Missimer and Ginsburg, 1998).
The rate of siliciclastic transport was initially
episodic and sufficiently low to minimize
interruption of the production of carbonates.
Differences in shoreline positions caused by
fluctuating sea levels allowed siliciclastics to
mix over a broad area. Mixing of the carbonates
and siliciclastics was achieved by tidal transport,
storms, longshore currents, bioturbation and
aeolian processes (Scott, 1988; Missimer and
Ginsburg, 1998; Missimer, 2002). Missimer and
Ginsburg (1998) list three important factors that
allowed the homogenized, co-deposition of
Arcadia Formation carbonates and siliciclastics
to occur: 1) a relatively slow rate of siliciclastic
sediment influx, 2) the lack of mud or clay, and
3) marine transport without river or stream
transport. Freshwater input would have caused
an increase in finer-grained siliciclastics (e.g.,
silts and clays), increased turbidity and
decreased salinity, all of which would have
diminished carbonate production.
Noteworthy topographic features occur along
the surface of the Arcadia Formation. In the
Tampa Bay area, interpreted seismic data
indicate subsurface relief of up to -197 ft (60 m;
Hine et al., in press). These features are
attributed to "spatially restricted, semi-enclosed,
siliciclastic-filled karst" that may coalesce into
larger collapse systems (Hine et al., in press). A
karst basin identified in their study due south of
the Pinellas County peninsula in Tampa Bay
correlates well with a trough extending
northward into the peninsula (Plate 45; see also
Tampa Member surface map, Plate 49).
Along the southern part of the Lake Wales
Ridge, the Arcadia Formation deepens sharply
(Plate 45). This elongate depression (or trough)
also occurs in the overlying Peace River
Formation (Plate 51). Although topographic
relief of the troughs are similar (-175 to -200 ft;
-53 to -61 m), the Arcadia Formation exhibits
little evidence of thinning, unlike the Peace
River Formation (Plate 52). Periods of erosion
(scouring?) or non-deposition owing to sea-level
fluctuations and paleo-ocean currents are likely
factors contributing to the origin of this trough.
Miocene-Pliocene structural control of the
feature is not indicated by the thickness of either
formation. The thickness of post-Hawthorn
Group sediments (see Plate 55 for
approximation) suggests that the trough may
have become a depoaxis for Pliocene-
Pleistocene siliciclastics.
A third significant topographic feature occurs
in south-central Charlotte County, where the
surface of the Arcadia Formation deepens to
more than 200 ft (60.9 m) MSL and notably
thickens to more than 700 ft (213 m; Plates 45
NDRTH T33S T34S
HH
ROMP 39
V-16740
Plate 37: Cross section: HH-HH' Manatee, Sarasota, and Charlotte Counties
T34S T35S T35S T36S T36S T37 S T375 T38S T38S T39S
FORT d
MANATEE CRAWFORD o
RIVER CREEK U
MYAKKA
I I S RIVER
T39S T40S
CSX RR
ROMP 33 ROMP 23 ROMP 18-1
V-16784 W-14382 W-14383
150-- 40
100 - 30
0 -- 20
50 -
10
0 o 0
- 10
- 50 -
FEET METERS
150 -4
40
100
50
0 0
- 50 20
- 100
-40
- 150
-200 60
-250
-80
- 300 -
-100
-400 -120
-450 -
-140
-160
-550
S-180
- 600 -
-700 0
-750
800 -240
- 850 -e6a
-900 -
-280
-950
-300
-1000 -
-1050 -320
AVON PARK
FORMATION
T.D. = 1600' BLS
SOUTH
HH'
LEVIS
CREEK
TR 2-1
V-15333
0 100 200
GAMMA (CPS)
UP UDSC
P PEACE RIVER
P FORMATION
P,M
C ,,M ARCADIA
ARCAM IA FORMATION
P:S.Ch
1) M TAMPA MEMBER
MCD.ChAp ARCADIA FORMATION
D,M.
DMPL / -- -
N SPL
C;IR ARCADIA FORMATION
M SUWANNEE
MR J LIMESTONE
MD
M
HiH
M,D H
0 SPL
M
M
M.D OCALA
M:D LIMESTONE
M
0
0 150 300
GAMMA CCPS)
TL, UDSC
-_-,T PEACE RIVER
Ss Mh \ FORMATION
S MP,p, S,S
M.Dp,PTD
M C,T,P,D
P, ,,T
M,p ,
M,Tp
C,TMp,P
M,D.P
MD,L ARCADIA
M,C,p,D,O FORMATION
P.S
TL
S Dp,M
MCP
TM,p,CL:P
TM
MD,T
SUVANNEE
LIMESTONE
150-- 40
100 - 30
20
50
10
0 -- 0
10
- 50
FEET METERS
150 -4
40
100 -
50 -
0 0
- 50 -
- 100 -
- 150 -
-200- -60
-050-
-300-
100
-350 -
-400 -120
-450
-140
- 500
-160
-550
S-180
-650 -20
-0-700 0
-750
800 -240
-850 -260
-900 -
-280
-950
-300
-1000 -
-1050 -320
BULLETIN NO. 68
HYDROGEOLOGIC FRAMEWORK OF THE SOUTHWEST
FLORIDA WATER MANAGEMENT DISTRICT
By Jonathan D. Arthur, (P.G. #1149), Cindy Fischler (P.G. #2512), Clint Kromhout (P.G. #2522),
James M. Clayton, (P.G. #381), G. Michael Kelley (P.G. #249), Richard A. Lee (P.G. #956), Li Li,
Mike O'Sullivan (P.G. #2468), Richard C. Green (P.G. #1776), and Christopher L. Werner (P.G. #2366)
INTRODUCTION
Background
Groundwater comprises approximately 85
percent of the total water-resource supply in the
Southwest Florida Water Management District
(SWFWMD), where existing water demands are
on the order of 435 billion gallons per year
(Southwest Florida Water Management District,
2006a). By 2025, the population of the region is
expected to increase more than 30 percent,
placing further demands on water resources.
Development of alternative water supplies and
continued water-resource management and
conservation are critically important toward the
sustainability of groundwater resources within
the aquifer systems of southwest Florida. These
practices, however, require the accumulation,
management and interpretation of
hydrogeological data.
In the mid-1990's, the SWFWMD and the
Florida Department of Environmental Protection
- Florida Geological Survey (FDEP-FGS)
entered into a cooperative project to develop a
series of geologic and hydrogeologic cross
sections throughout the 16-county SWFWMD
region. The project was designed to characterize
the relation and extent of lithostratigraphic1 and
hydrostratigraphic2 units within the region with
an emphasis on use of hydrogeologic data
collected by the District's Regional Observation
and Monitor-well Program (ROMP). This project
was later expanded to include production of
surface and thickness maps of the units
represented in the cross sections.
To accomplish the goal of the regional cross
section project, the District was divided into four
study areas (three project phases): Phase IA
includes Pinellas and Hillsborough Counties;
Phase IB includes Manatee, Sarasota, Hardee,
DeSoto and Charlotte Counties; Phase II includes
the northern part of the District, from Levy,
Marion and Lake to Pasco Counties; and Phase
III includes the southeastern part of the District,
encompassing all areas not covered in Phases IA,
IB and II. Interim reports were published for
Phase IA and II (Green et al., 1995 and Arthur et
al., 2001a, respectively). Rather than separately
publishing reports for the remaining phases, the
cross sections are incorporated in this report.
Purpose and Scope
The purpose of this study is to refine the
hydrogeological framework of the region to
facilitate science-based decision making with
regard to the protection, conservation and
management of southwest Florida's water
1 Lithostratigraphic units are laterally extensive
sequences of rocks and sediments reflecting unique
lithologic characteristics; each unit was deposited
within a generally similar paleo-environment during
a given period of time in Earth's history.
2 Hydrostratigraphic units include laterally extensive
sequences of rocks and sediments that are related by
hydrogeologic characteristics. Hydrostratigraphic
units may or may not correlate with lithostratigraphic
units.
FLORIDA GEOLOGICAL SURVEY
packstone with varying amounts of quartz sand
and clay (Scott, 1988). Minor phosphate (less
than 3 to 5 percent), dolomite and chert
(siliceous limestone, silicified corals; see also
Upchurch et al., 1982) are also observed. Fossil
molds of foraminifera, mollusks, gastropods and
algae are all common within the Tampa Member
(Scott, 1988). Pinkish gray to light olive gray
dolostones also occur with a similar accessory
mineral assemblage and fossil assemblage as the
limestones. Thin sand and clay beds can be
found sporadically within the unit (Scott, 1988).
Porosity of the Tampa Member is generally
intergranular and moldic, with measured total
porosity values (17 samples) ranging from 10.4
percent to 49.6 percent, averaging 32.3 percent
(median value =33.6 percent).
The subcrop limit of the Tampa Member
extends from Pasco County to the northernmost
part of Charlotte County and eastward into the
western half of Polk, DeSoto and Hardee
Counties (Plate 49 and 50). The top of the
Tampa Member ranges from more than 100 ft
(30.5 m) MSL in Pasco County to deeper than -
350 ft (-107 m) MSL in Sarasota County (Plate
49) and exhibits variable thickness. The
maximum observed thickness of the Tampa
Member is 292 ft (89.0 m) (Plate 17; W-14882
[TR 6-1]); however, some would propose that
the lower Tampa Member in this well is more
characteristic of the undifferentiated Arcadia
Formation.
In the northern third of its extent, the Tampa
Member overlies the Suwannee Limestone and
the contact appears to be locally conformable.
In Pinellas and northwest Hillsborough
Counties, for example, samples have been
informally referred to as "SuwTampaHaw" due
to the subtle transition between the units. In the
central and southern regions, this unit overlies
the Arcadia Formation (undifferentiated), or the
Nocatee Member of the Arcadia Formation. In
many wells, the transition between the Tampa
Member and the underlying Arcadia Formation
is gradational, with phosphorite content
increasing with depth. The Tampa Member is
conformably overlain by the Arcadia Formation
(undifferentiated) in many areas (e.g., Plate 14);
however numerous exceptions exist. In parts of
Pasco and northern Hillsborough Counties, the
unit is unconformably overlain by UDSC or
undifferentiated clay-rich Hawthorn Group
sediments. East of this area, the Tampa Member
is unconformably overlain by the Peace River
Formation. Toward the east and south, the
Tampa Member facies grades laterally into the
Arcadia Formation. In Sarasota County, the unit
appears to grade laterally into the Nocatee
Member as it becomes increasingly more sandy.
Scott (1988) also reports this lateral facies
change in northern Hardee County.
The Tampa Member generally exhibits
variable gamma-ray activity (Figure 10; Arthur
et al., 2001a) that limits the value of this log to
discern unit boundaries. For example, when
underlain by the Arcadia Formation
(undifferentiated), the Nocatee Member or the
Suwannee Limestone, it is difficult to
distinguish these units from the Tampa Member
based on gamma-ray activity. On the other
hand, where the Tampa Member is overlain by
the Arcadia Formation, the two units are usually
readily distinguishable due to higher gamma-ray
activity in the undifferentiated Arcadia
Formation.
Along the updip erosional pinchout of the
Tampa Member, where it forms an irregular
subcrop contact with the Suwannee Limestone
(Plate 49), the top of the FAS generally
coincides with the uppermost carbonate unit
occurrence (Figure 8). In the west-central part
of the study area, the Tampa Member is the
uppermost lithostratigraphic unit within the FAS
(Figure 8); however, based on lithologic and
hydrologic data from wells in south-central
Hillsborough County, the Tampa Member is
locally hydraulically separated from the
Suwannee Limestone and is therefore considered
part of the IAS/ICU (Figure 8). This latter
hydrogeologic setting occurs locally in northern
Pinellas County as well.
The depositional environment of the Tampa
Member was that of a quiet water lagoon, much
like present day Florida Bay (King, 1979). An
influx of siliciclastics nearly devoid of
phosphorite distinguishes Tampa Member
deposition from older and younger Hawthorn
Group units in the stratigraphic section.
FLORIDA GEOLOGICAL SURVEY
Hydrostratigraphy
Introduction
The hydrostratigraphic setting of the study
area varies from a locally exposed single aquifer
system in the north, to three aquifer systems in
the central and southern parts of the study area.
In the northern region, the FAS ranges from
variably confined to unconfined; clayey
sediments of the IAS/ICU or basal SAS are
locally present; IAS/ICU confining sediments
are present especially within the uplands and
ridges. The SAS, where present, is intersected
by numerous karst features (Trommer, 1987; see
also Plate 3) which may act as direct hydraulic
connection between the SAS and the FAS.
Increased permeability of the IAS/ICU occurs
where the Hawthorn Group sediments thicken
southward from central Hillsborough and Polk
Counties. In the central and southern regions,
the IAS/ICU collectively forms a thick confining
unit with intervening permeable zones that
separate the FAS from the SAS. As noted
earlier, the nomenclature applied herein is based
on aquifer system nomenclature as modified
from Florida Geological Survey Special
Publication 28 (see Hydrogeology, p. 17;
Appendix 2).
Hydrogeological properties
Numerous studies provide details on
hydrogeologic properties of aquifer systems in
the study area. For detailed information on
aquifer transmissivity, storativity, leakance
coefficients, etc., the reader is referred to USGS
publications (e.g., Ryder, 1985; Wolansky and
Corral, 1985; Metz, 1995; Yobbi, 1996;
Knochenmus, 2006), numerous SWFWMD
ROMP technical reports (e.g., Clayton, 1994,
1999; Gates, 2001; LaRoche, 2004); SWFWMD
hydrogeological studies (e.g., Barcelo and
Basso, 1993; Hancock and Basso, 1993; Basso,
2002, 2003) and especially the Southwest Florida
Water Management District (2006b) compilation:
"Aquifer Characteristics within the Southwest Florida
Water Management District, July 2005."
To provide a general characterization of these
hydrogeologic parameters, two datasets are
statistically and graphically summarized in the
discussion of each aquifer system: 1) data in
Southwest Florida Water Management District
(2006b) that meet certain quality
assurance/quality control (QA/QC) standards6
and 2) results of more than 200 hydraulic
conductivity and total porosity analyses
measured at the FDEP-FGS on cores from
within the study area. Both datasets are
presented to represent laboratory and field-scale
conditions. The Southwest Florida Water
Management District (2006b) compilation
represents properties measured during aquifer
pumping and performance tests, while the
FDEP-FGS dataset represents matrix
permeability (vertical) and porosity of core
samples. In Florida's dual-porosity (e.g,
intergranular and conduit flow) heterogeneous
carbonate terrain, it is widely recognized that
permeability calculated from field-scale aquifer-
test data (e.g., Basso, 2002) may differ by orders
of magnitude from that of laboratory
measurements. These data summaries are
presented herein to characterize expected ranges
of these parameters for use in hydrologic models
and to provide a frame of reference for those
collecting hydrological data in the field or lab.
For further details on matrix permeability, as
well as discussion of its significance and
limitations, the reader is referred to Budd (2001,
2002) and Budd and Vacher (2004).
In the descriptive statistics for each aquifer
system, standard parameters are summarized,
including mean, median, range, quartile values,
and number of analyses. Also included are
distribution descriptors: skewness, kurtosis and
6 QA/QC screening guidelines: 1) used data with
"acceptable" and "good" test-reliability scores as
defined and assigned in Southwest Florida Water
Management District (2006b); 2) avoided aquifer
tests where partial penetration was noted and no
corrections applied; 3) avoided tests where aquifer
penetration thicknesses were inconsistent with casing
and total depth data; 4) avoided use of well pairs in
which the observation well open interval differed
from the open interval in the test well by more than
15 percent; 5) avoided short-duration tests; and 6)
evaluated comments with respect to quality of test
data.
FLORIDA GEOLOGICAL SURVEY
Ryder, P.D., Johnson, D.M., and Gerhart, J.M., 1980, Model evaluation of the hydrogeology of the
Morris Bridge Wellfield and vicinity in west-central Florida: U.S. Geological Survey Water
Resources Investigations Report 80-29, 92 p.
Sacks, L.A., 1996, Geochemical and isotopic composition of groundwater with emphasis on sources of
sulfate in the upper Floridan aquifer in parts of Marion, Sumter and Citrus Counties, Florida: U.S.
Geological Survey Water-Resources Investigations Report 95-4251, 47 p.
Sacks, L.A., and Tihansky, A.B., 1996, Geochemical and isotopic composition of groundwater, with
emphasis on sources of sulfate in the upper Floridan aquifer and intermediate aquifer system in
southwest Florida: U.S. Geological Survey Water-Resources Investigations Report 96-4146, 54 p.
Schmidt, W., 1997, Chapter 1 Geomorphology and physiography of Florida, in Randazzo, A.F., and
Jones, D.D., eds., The Geology of Florida: Gainesville, University Press of Florida, p. 1-12.
Scott, T.M., 1978, Environmental Geology Series Orlando Sheet: Florida Geological Survey Map
Series 85, scale: 1:250,000, 1 sheet.
1979, Environmental Geology Series Daytona Beach Sheet: Florida Geological Survey, Map
Series 93, scale 1:250,000, 1 sheet.
1988, The lithostratigraphy of the Hawthorn Group (Miocene) of Florida: Florida Geological
Survey Bulletin 59, 148 p.
1991, A geological overview of Florida, in Scott, T.M., Lloyd, J.M., and Maddox, G., eds.,
Florida's Groundwater Quality Monitoring Program Hydrogeological Framework: Florida
Geological Survey Special publication 32, p. 5-14.
1992a, Chapter 3-Hydrostratigraphy, in Maddox, G.L., Lloyd, J.L., Scott, T.M., Upchurch, S.B.,
and Copeland, R., Florida's groundwater quality monitoring program Background
hydrogeochemistry: Florida Geological Survey Special Publication No. 34, p. 6-12.
1992b, A geological overview of Florida: Florida Geological Survey Open-File Report 50, 78 p.
S1992c, Coastal plains stratigraphy: the dichotomy of biostratigraphy and lithostratigraphy A
philosophical approach to an old problem, in Scott, T.M., and Allmon, W.D. eds., Plio-
Pleistocene stratigraphy and paleontology of southern Florida: Florida Geological Survey Special
Publication 36, p. 21-23.
1993, Neogene lithostratigraphy of the Florida peninsula problems and prospects, in Zullo,
V.A., et al., eds., The Neogene of Florida and adjacent regions: Florida Geological Survey
Special Publication 37, p. 1-2.
1997, Chapter 5-Miocene to Holocene history of Florida, in Randazzo, A.F., and Jones, D.D.,
eds., The Geology of Florida: Gainesville, University Press of Florida, p. 57-67.
2001, Text to accompany the geologic map of Florida (MS 146): Florida Geological Survey
Open-File Report 80, 29 p.
2004, The new geomorphic map of Florida: Geological Society of America Abstracts with
Programs, v. 36, no. 5, p. 578.
FLORIDA GEOLOGICAL SURVEY
Sediments comprising the SAS are
predominately post-Hawthorn in age and
generally consist of some combination of sands
shells and clays. In parts of the northern District
where the IAS/ICU is not laterally extensive,
discontinuous clay lenses serve as basal SAS
confinement, locally separating the SAS from
the FAS. Some of these basal clays may be
erosional remnants of (and correlative with)
lithostratigraphic units comprising the IAS/ICU.
In areas where Pliocene clayey sediments (see
clayeyy sand," Figure 4) are exposed at or near
land surface, such as west-central Polk County,
the SAS or water-table aquifer may not be
present; instead, the setting reflects IAS/ICU
overlying the FAS. Where hydraulic continuity
exists between uppermost Hawthorn Group
sands and younger sediments, the SAS includes
those sands, which are generally less than 20 ft
(6.1 meters) thick. In the southernmost part of
the study area, the Ft. Thompson and
Caloosahatchee Formations and upper
permeable sediments of the Tamiami Formation
comprise the SAS. Although mapping of these
complex "post-Hawthorn" units is beyond the
scope of this study, research did focus on the
depth and extent of clays within the Pliocene
Tamiami Formation, which are significant as
they comprise the base of the SAS in the region
(e.g., Reese, 2000; Weinberg and Cowart, 2001).
The IAS/ICU occurs throughout most of
Florida (Scott, 1992a) and correlates with
aquifer systems in parts of Georgia and
Alabama. In the study area, it is comprised of
mid- to upper Oligocene Pliocene sediments
and is generally continuous south of Pasco
County. As this hydrostratigraphic unit thickens
southward, interlayered permeable carbonates
become important water-producing zones,
especially south of Manatee County where the
FAS water becomes less potable. In this area,
three permeable zones are present; however,
correlation and mapping of these zones is
difficult, even with the use of hydrochemical
parameters (Knochenmus and Bowman, 1998;
Torres et al., 2001; Knochenmus, 2006). North
of Hillsborough County, the IAS/ICU
predominantly occurs within the uplands and
ridges, where it functions hydrologically as a
semi-confining to confining unit.
The FAS is one of the most productive
aquifers in the world. It underlies all of Florida,
southern Georgia and small parts of Alabama
and South Carolina for a total area of about
100,000 mi2 (-259,000 km2) (Johnston and
Bush, 1988). In parts of southwest Florida,
south from Sarasota, Charlotte, Glades and Lee
Counties, the FAS contains mineralized, non-
potable water. As a result, relatively permeable
zones within the IAS/ICU comprise the main
source of water supply (Miller, 1986; Torres et
al., 2001) in this region. The FAS is confined
except in parts of the northern third of the study
area where it occurs at or just below land surface
(Ryder, 1985). Throughout the study area, the
FAS predominately consists of carbonate rocks
(Southeastern Geological Society, 1986) ranging
in age from Paleocene to Miocene.
METHODS
Sample Description
More than 250 detailed lithologic de-
scriptions of borehole cores and cuttings were
completed for this study. These descriptions
record standard rock, mineral, fossil and textural
features. Selected parameters include color,
induration, grain size and range, sorting,
roundness, mineral percentages and special
descriptive, depositional or sedimentary
features. Descriptions of carbonate material
were based on the Dunham (1962) classification
system, which focuses on depositional texture
and whether the rock is mud-supported or grain-
supported: 1) mudstone muddy carbonate rock
containing less than 10 percent grains, 2)
wackestone mud supported rock containing
more than 10 percent grains, 3) packstone grain
supported muddy carbonate, 4) grainstone -
mud-free carbonate rock which is grain
supported and 5) boundstone carbonate rock
showing signs of being bound (e.g. cementation)
during deposition and reflecting original position
of growth. It should be noted that the Dunham
(1962) classification considers a "grain" as
having a diameter greater than 20 microns, while
"mud" is less than 20 microns. As a result, a
very fine grained grainstone may appear as a
mudstone even under a low-power binocular
microscope (David Budd, 2004, personal
FLORIDA GEOLOGICAL SURVEY
Arthur, J.D., Cowart, J.A., and Dabous, A.A., 2001b, Florida aquifer storage and recovery geochemical
study: year three progress report: Florida Geological Survey Open-File Report 83, 46 p.
Arthur, J.D., Wood, H., Baker, A.E., Cichon, J.R., Raines, G.L., 2007, Development and implementation
of a Bayesian-based aquifer vulnerability assessment in Florida: Natural Resources Research, vol.
16, p. 93- 107.
Arthur, J.D., Baker, J., Cichon, J., Wood, A., and Rudin, A., Florida Aquifer Vulnerability Assessment
(FAVA): Contamination potential of Florida's principal aquifer systems: Florida Geological
Survey Bulletin 67, (in review).
Back, W., and Hanshaw, B.B., 1970, Comparison of chemical hydrogeology of the carbonate peninsulas
of Florida and Yucatan: Journal of Hydrology, v. 10, p. 330-368.
Barcelo, M., and Basso, R., 1993, Computer model of groundwater flow in the eastern Tampa Bay Water
Use Caution Area: Brooksville, Southwest Florida Water Management District, 102 p.
Barnett, R.S., 1975, Basement structure of Florida and its tectonic implications: Transactions of the Gulf
Coast Association of Geological Societies, v. 25, p. 122-142.
Barr, G.L., 1996, Hydrogeology of the surficial and intermediate aquifer systems in Sarasota and adjacent
counties, Florida: U.S. Geological Survey Water-Resources Investigations Report 96-4063, 22 p.
Bass, M.N., 1969, Petrography and ages of crystalline basement rocks of Florida: American Association
of Petroleum Geologists Memoir no. 11, p. 283-310.
Basso, R., 2002, Hydrostratigraphic zones within the Eastern Tampa Bay Water Use Caution Area:
Brooksville, Southwest Florida Water Management District, 34 p. plus appendices.
,2003, Predicted change in hydrologic conditions along the Upper Peace River due to reductions
in groundwater withdrawals: Brooksville, Southwest Florida Water Management District, 53 p.
2004, Hydrogeologic setting of lakes within the Northern Tampa bay region: Brooksville,
Southwest Florida Water Management District Technical Memorandum (November 9), 27 p.
Bemdt, M.P., Oaksford, G.M., and Schmidt, W., 1998, Chapter 3-Groundwater: in Fernald, E.A. and
Purdum, E.D., eds., Water Resources Atlas of Florida: Tallahassee, Florida State University,
Institute of Science and Public Affairs, 312 p.
Braunstein, J., Huddlestun, P., and Biel, R. (eds.), 1988, Gulf Coast Region: Correlation of stratigraphic
units in North America (COSUNA) project: Tulsa, American Association of Petroleum
Geologists, 1 sheet.
Brewster-Wingard, G.L., Scott, T.M., Edwards, L.E., Weedman, S.D., and Simmons, K.R., 1997,
Reinterpretation of the peninsular Florida Oligocene: an integrated stratigraphic approach:
Sedimentary Geology, v. 108, p. 207-228.
Broska, J.C., and Barnette, H.L., 1999, Hydrogeology and analysis of aquifer characteristics in west-
central Pinellas County, Florida: U.S. Geological Survey Open-File Report 99-185, 23 p.
BULLETIN NO. 68
Figure 34. Statistical summary of UFA storativity data from Southwest Florida Water
Management District (2006b). Asterisks in the box plot denote statistical outliers.
Figure 35. Statistical summary of UFA leakance data from Southwest Florida Water Management
District (2006b). Asterisks in the box plot denote statistical outliers.
Summary for UFA S
0.000 0.016 0.032 0.048 0.064 0.080 0.096
95% Confidence Intervals
Mean- I
Median-
0.000 0.001 0.002 0.003 0.004 0.005
A nderson-Darling Normality Test
A-Squared 24.66
P-Value < 0.005
Mean 0.002660
StDev 0.010812
Variance 0.000117
Skew ness 6.6858
Kurtosis 47.7119
N 81
Minimum 0.000000
1st Quartile 0.000265
Median 0.000640
3rd Q uartile 0.001200
M aximum 0.086000
95% Confidence Interval for Mean
0.000269 0.005050
95% Confidence Interval for Median
0.000404 0.000935
95% Confidence Interval for StDev
0.009365 0.012792
Summary for UFA L (per day)
0.000 0.012 0.024 0.036 0.048 0.060 0.072
95% Confidence Intervals
Mean- I-
Median- t-
0.000 0.001 0.002 0.003 0.004 0.005 0.006
Anderson-Darling Normality Test
A-Squared 15.47
P-Value < 0.005
Mean 0.003141
StDev 0.010668
Variance 0.000114
Skew ness 5.6131
Kurtosis 33.5295
N 59
Minimum 0.000029
1st Q uartile 0.000147
Median 0.000300
3rd Q uartile 0.001800
Maximum 0.072380
95% Confidence Interval for Mean
0.000361 0.005921
95% Confidence Interval for Median
0.000241 0.000567
95% Confidence Interval for StDev
0.009031 0.013036
FLORIDA GEOLOGICAL SURVEY
3) hydrogeologic characteristics of the samples
(e.g., estimated porosity and permeability,
hydraulic continuity between lithostratigraphic
units), 4) potentiometric data from nested
monitor wells, and 5) in the absence of other
data, correlation to lithostratigraphic units.
Application of the first four methods is highly
preferred; the majority of this data originates
from ROMP wells.
Contacts between aquifer systems can be
very subtle or abrupt depending on the
hydrogeologic properties of the rocks and
sediments. When only lithologic material from
a borehole is available on which to base an
aquifer-system boundary, further complications
arise. Preferential removal of clay-sized
particles, either during drilling or sample
archiving (e.g., sorting during material transfer
or washing of cuttings), tend to bias toward
interpretations of higher sample permeability.
Delineation of the basal contact of the SAS is
perhaps the most susceptible to the
aforementioned bias. If the contact is based
solely on estimates of hydrogeologic properties
of lithologic data, misrepresentation of clay
content, especially in borehole cuttings may
result in the interpretation of a preferentially
deep base of the SAS. This issue may become a
factor where the SAS may include sediments as
old as the upper Hawthorn Group. On the other
hand, permeable sands along the top of the upper
Peace River Formation in Manatee County (Tom
Scott, personal communication, 2006) comprise
the lower part of the SAS. If there is reason to
believe that the two units (Hawthorn and post-
Hawthorn Group sediments) are hydraulically
connected, both would be considered part of the
SAS. Alternatively, sandy clays overlying clay-
rich Hawthorn Group sediments would be
considered part of the IAS/ICU (assuming
sufficient lateral extent). Further south, the
Tamiami Formation is included within both the
SAS and IAS/ICU.
Noting the above exceptions, the lateral
extent of the IAS/ICU broadly corresponds to
the extent of Hawthorn Group sediments, except
where those sediments are part of the FAS (e.g.,
the Tampa Member [Arcadia Formation] along
the upper reaches of the Hillsborough River).
For consistency, in areas where the IAS/ICU is
mapped owing to sufficient lateral continuity,
the SAS is mapped over the same extent. In
areas where the SAS and IAS/ICU are
discontinuous, the FAS is generally
characterized as unconfined to semi-confined
(see Hy ,,, i'ui gi ph 1 ', p. 52, for more detail).
Figure 8 represents a compilation of
hydrogeological data to provide correlation
between hydrostratigraphic units and
lithostratigraphic units. In most areas, the
correlation is readily apparent, such as the
relation between the top of the Suwannee
Limestone in Sarasota County with the top of the
FAS. In another example, the Tampa Member
(Arcadia Formation) is hydraulically connected to
the FAS in Pinellas County and therefore
comprises the uppermost part of the FAS. The
correlations, however, are not always
straightforward, such as the area denoted as
"variable" (Suwannee Limestone and Nocatee
Member, Arcadia Formation) in DeSoto County
(Figure 8).
Cross-Section Construction
Detailed lithologic descriptions, gamma-ray
logs and hydrologic data comprise the bulk of the
information used to develop the cross sections.
The dominant sources of information for cross-
section control are SWFWMD ROMP wells;
FDEP-FGS wells were included to fill out
appropriate data-point coverage for the cross
sections. Where no lithologic data was available,
borehole geophysical logs were used. Of these
geophysical logs, gamma-ray logs were the most
readily available and generally useful for
correlative purposes within the study area.
Gamma-ray logs were included in the cross
sections to allow comparison of the gamma-ray
signatures relative to each stratigraphic unit. The
following discussion outlines the methods used
for construction of the cross sections for this
study.
Topography
Topographic profiles were included on each
cross section to facilitate comparison of surface
morphologies with subsurface stratigraphy. Data
used to construct these profiles was taken from U.S.
Geological Survey 1:24,000 (7.5 minute) quadrangle
maps. The profiles include selected anthropogenic
features, cultural boundaries and landforms.
FLORIDA GEOLOGICAL SURVEY
association can be locally complex and
indistinct. In either case, the relationship
depends on the degree of hydraulic continuity
between and among lithostratigraphic units. The
variable hydrogeologic setting in the northern
region serves as an example: characterization of
the SAS (water-table aquifer) is complicated by
lateral hydraulic discontinuities. Regionally, the
water table may reflect the potentiometric
surface of the unconfined FAS (e.g., west of the
Brooksville Ridge); however, local hydraulic
separation between the SAS and the FAS may
exist. As a result, delineation of a regionally
extensive SAS that is significant as a water-
producing unit is the subject of some debate.
The framework of stratigraphy and
hydrogeology developed during this
investigation serves as a foundation for
numerous applications, ranging from more
refined hydrogeological mapping to mineral
resource assessments, well-field designs and
groundwater models. Regardless of the
application, it is our hope that this study
facilitates science-based decision making
regarding the protection, conservation and
management of the solid-earth and water
resources of southwestern Florida.
BULLETIN NO. 68
Geomorphology
0 5 10 20 30 40
Miles
0 5 10 20 30 40
N Kilometers
Scale 1 1,750,000
Projection: Custom FDEP Albers
[Silver Glen. I
~0 o/
I Alexander
Gulf
o f Chassahowitsh
Mexico WeekiWa
S 0
0
r 0
0
Explanation
|J |Study Area
- Water Management Districts
Springs (1st Magnitude)
o Springs
= Geomorphology
Desoto Plain
I
r-
Caloosahatchee Inch
Figure 6. Geomorphology of the study area (from White, 1970 and Puri and Vernon 1964). Spring
locations from Scott et al. (2004).
FLORIDA GEOLOGICAL SURVEY
Topography
of South-Central
Florida
0 5 10 Miles
0 5 10 Kilometers
Projection: Custom FDEP Albers
Explanation
S| Counties
Lake Wales Ridge
310ft
I 155 ft
oft
Figure 7. Shaded topographic relief of the southern extent of the Lake Wales Ridge.
Area
of -
Interest
FLORIDA GEOLOGICAL SURVEY
Floridan aquifer system
Overburden Thickness
0 5 10 20 30 40
mm Miles
0 510 20 30 40
Kilometers
Scale 1:1,750,000
Projection: Custom FDEP Albers
"U
I
I
I
* S
1 -~
Explanation
| Study Area
- Water Management Districts
FAS Overburden Thickness
*900 ft
450 ft
Figure 31. Floridan aquifer system overburden thickness as predicted from geospatial modeling
(i.e., DEM minus top of FAS). The map is not contoured due to extreme resolution differences in
source grids.
Gulf
of
Mexico
I
-- I
I ~*,*, I
- -
SURFICIAL AQUIFER
THICKNESS
0 5 10 20 30
0 510
20 30 40
SYSTEM
Miles
Kilometers
Scale: 1:1,000,000
Contour Interval: 25 ft
Projection: Custom FDEP Albers
Gulf
of
Mexico
0
0
0 o
0
o
Explanation ,o
Study Area \
Wells Used
z -- Contours
j/2/ Discontinuous Basal Confinement of SAS
- Water Management Districts
SAS Thickness (ft.)
*>275
140
f
6m,
I
I
I
r
I
I
I
I
I L
IJ
1* 1
PLATE 55
I
M003MMMK::: I
0 0 ;
o //
0 0
0
I
8230'W 82W
I I
I-
1
4'
1
SI
SI
81 30'W 81 W
I I
Bone Valley Member
of the Peace River
Formation Surface
0 5 10
20 30
Miles
0 0 2Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 30 ft
Projection:
Custom FDEP Albers
Gulf
of
Mexico
I
I-I
-~l l
I0
- -
o oo
Explanation
W Study Area
Wells Used
Contours
S- Bone Valley Mbr. Extents
- Water Management Districts
Bone Valley Mbr. Surface (ft. MSL)
>120
--- -
'4
0
o\ 0
\m\
0 0
\eea
~~1
PLATE 53
83W
m i.
.I
I
I
I
-n,
CD
% CD
-q
I
I
I
FLORIDA GEOLOGICAL SURVEY
ROMP 17
W-15303
Figure 10. Characteristic gamma-ray (y) log responses.
ROMP 31
W-13514
Plate 29. Cross section: Z-Z' Levy, Citrus, Pasco, and Hernando Counties
T14IS IT15S
@
T1Sl TI6S
W-15075
Ti6S T17S
TI 7S IT18S
T18sIT9S
T19S T20S
W-720
T20S T1S
ROMP 108 C
W-15685
T1S IT22S
22SIT23S
TR 19-3
W-14873
25 50 75
AMMA (CPS)
C.O ^ HAWTHORN GROUP
cHo' UNDIFF. UDSC
S'l
MCS.I OCALA
0:81 LIMESTONE
M,R.I
MRI
Is:c. .o
MD.R.I {AVON PARK
:RIMRI FORMATION
bR
s 01
MC,0,C
C'DM,'D,C,0
LIMCDTG
R;::
M,D, CO
UDSC
OCALA
LIMESTONE
c/
c
c
c
c
M.DP
N,D
NO SPL
R
NO SPL
NO SPL
AVON PARK
FORMATION
UDSC
AVON PARK
FORMATION
UDSC
OCALA
LIMESTONE
AVON PARK
FORMATION
EXPLANATION
HATCHING PATTERNS
GRAVEL FINE MEDIUM COARSE
DOLOSTNE AUIFEN R SRSDTEM/
IONFINING UNIT
IN FLORIDAN
SAND RNE MEDIUM COARSE AQUIFER
INTERBEDDED LIMESTONE AND DOLOSTONE
SILT FINE MEDIUM COARSE
COMMENTS
SILT
CLAY
SHELL
DOLOSTONE
UMESTONE
HEAVY MINERALS
NO SAMPLE
GYPSUM
PYRTE
MICRITE
SAND
PHOSPHATE GRAVEL
PHOSPHATE SAND
ORGANIC
SPAR
IRON STAIN N
QUARTZ
ANHYDRlTE
CHERT
100 -
L --- - --
rS0 250 500
0 10 20 30 0 25 50 GAMMA (CPS)
GAMMA (CPS) R GAMMA (CPS) NO STALE AVAILABLE u sco OELPI)
DAMA LOG
UDSC 0COO ) ,LI
TD = 4
NO SPL
0
0
0
M,D,O
M,O
M.D,O
HORIZONTAL SCALE
MILES
a 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGE oRATION S APPROXIMATELY
100 -IES HORIZONTA- CL
* OVERLAPPING LOGS SEMI-CONFINED TO UNCONFNED
FOR THIS INTERVAL FLORIDAN AQUIFER SYSTEM
OMlI7ED.
CLAY CHERT SHELL BED SUM
AVON PARK
FORMATION
ID 490' BLS
ST
NORTH
T13sITR4S
200- 60
50
150-
125-
100- 30
75 -
20
50 -
0 0
ROMP 131
W-15682
-200 -t- 60
23S 7T24S
T24S| T25S
SOUTH
Z'
T25S T26S
TR 18-2
W-15649
400 -120
-450 -
-650 -L oD
--200
- 850 -260
TR 17-3
W-14675
20-- 60
50
150-
125- 40
100- 30
75 -
20
50 -
25:-
- 25 l-
FET METERS
2.D 6O
TR 16-2A
W-16609
-200 -- -
400 120
- 850 -2
POND
150 -
100 -
-150-
- BO
-100
7' BLS
-4N -
_50o -
-.D
-mo
- 70D -
-750
-wo
LOG OMITD
- -180
NO SPL
- 900 -
- 9o00--
- -2BO
- -280
BULLETIN NO. 68
include Joyner and Sutcliff (1976), Upchurch
(1992), Kauffman and Herman (1993), Broska
and Knochenmus (1996) and Torres et al.
(2001). Knochenmus (2006) characterizes the
water quality and hydraulic heterogeneity of the
intermediate aquifer system in the southern part
of the District. The study underscores that
previously defined "permeable zones" of this
aquifer system are hydraulically similar to
"semi-confining units" in the upper Floridan
Aquifer System. A statewide hydrochemical
assessment of the surficial aquifer system was
completed by Upchurch (1992).
Several groundwater flow models of the
SWFWMD region have been published (e.g.,
Ryder, 1985; Barcelo and Basso, 1993; Yobbi,
1996), most of which are discussed in the
comprehensive work of Sepulveda (2002),
wherein he developed a groundwater flow model
for peninsular Florida that includes the
Intermediate and Floridan aquifer systems.
Selected compilations of aquifer parameters on
which many of these models are based are
presented in Hydrogeological Properties, p. 52.
Physical Setting
Geology
Development of the Florida carbonate
platform primarily occurred during the Late
Cretaceous through middle Cenozoic and was
generally free of intermixed sands and clays.
Strong currents across northern Florida in a
feature broadly referred to as the Georgia
Channel System (Huddlestun, 1993) effectively
precluded transport and deposition of these
siliciclastics to the platform. During this period,
deposition of the Cedar Keys Formation,
Oldsmar Formation, Avon Park Formation,
Ocala Limestone, and the Suwannee Limestone
occurred. Huddleston (1993) proposed the
Georgia Channel System recognizing spatially
and temporally overlapping features (e.g.,
Suwannee Strait and Gulf Trough) proposed in
the literature that described paleotopography
(paleobathymetry) and associated paleocurrents.
Randazzo (1997) provides an overview of this
dynamic system and feature names.
During the Oligocene, the southern
Appalachians experienced uplift and erosion
(Scott, 1988). Southward transport and
deposition of ensuing siliciclastic sediments
began to fill the channel system, which allowed
ocean currents to transport sediments southward
across the well-developed carbonate platform.
As a result, some of the first siliciclastic
sediments in southern Florida carbonates appear
as sand lenses in the Lower Oligocene
Suwannee Limestone south of Charlotte County
(Missimer, 2002). The influx of siliciclastic
sediments, mixing with locally-formed
carbonates led to Late Oligocene through the
Early Pliocene deposition of the Hawthorn
Group (Scott, 1988; Missimer et al., 1994)
throughout most of Florida. In much of
peninsular Florida phosphate deposition
occurred yielding many economic phosphorite
deposits. This period of phosphogenesis is
described by Riggs (1979a, 1979b) and
Compton et al. (1993); [see Bone Valley
Member, p. 48, for more detail]. During the
Late Pliocene to Recent, sediment deposition
became even more siliciclastic dominant. Shell
beds were deposited along coastal areas and
migrated in response to sea-level fluctuations.
The geology and depositional environment of
lithostratigraphic units in the region are the
subject of numerous studies in southwestern
Florida; results of which are presented in the
Il, ii~i,,g,,il,!h'y section, p. 30, of this report.
From deposition of the Cedar Keys Formation
through Pliocene-Pleistocene shell beds, a
dynamic transition from carbonate to
siliciclastic-dominated depositional environments
is reflected.
The surface distribution of lithostratigraphic
units (Figure 2) in the study area is a function of
post-depositional influences ranging from
tectonic activity, platform stability, sea-level
changes and karst processes. For example, the
Avon Park Formation is the oldest exposed
lithostratigraphic unit in the study area (Figure
2). This Eocene unit gently dips southward
toward Charlotte County to depths exceeding
1500 ft (457.2 m) below land surface (BLS). In
PLATES (CONTINUED)
15. Cross section: L-L' Manatee, Hillsborough, and Polk Counties
16. Cross section: M-M' Manatee County
17. Cross section: N-N' Sarasota and Manatee Counties
18. Cross section: 0-0' Sarasota County
19. Cross section: P-P' Charlotte County
20. Cross section: Q-Q' Polk and Osceola Counties
21. Cross section: R-R' Hillsborough and Polk Counties
22. Cross section: S-S' Hillsborough and Polk Counties
23. Cross section: T-T' Manatee, Hardee, and Highlands Counties
24. Cross section: U-U' Manatee, Hardee, and Highlands Counties
25. Cross section: V-V' Manatee, DeSoto, Hardee, and Highlands Counties
26. Cross section: W-W' Sarasota, DeSoto, and Highlands Counties
27. Cross section: X-X' Sarasota, DeSoto, Highlands, and Glades Counties
28. Cross section: Y-Y' Charlotte and Glades Counties
29. Cross section: Z-Z' Levy, Citrus, Pasco, and Hernando Counties
30. Cross section: AA-AA' Marion, Sumter, Hernando, and Pasco Counties
31. Cross section: BB-BB' Pinellas County
32. Cross section: CC-CC' Hillsborough and Manatee Counties
33. Cross section: DD-DD' Hillsborough and Manatee Counties
34. Cross section: EE-EE' Lake, Polk, Hardee, DeSoto, and Charlotte Counties
35. Cross section: FF-FF' Polk, Highlands, and Glades Counties
36. Cross section: GG-GG' Manatee, Sarasota, and Charlotte Counties
37. Cross section: HH-HH' Manatee, Sarasota, and Charlotte Counties
38. Avon Park Formation surface
39. Ocala Limestone surface
40. Ocala Limestone thickness
41. Suwannee Limestone surface
42. Suwannee Limestone thickness
43. Hawthorn Group surface
44. Hawthorn Group thickness
45. Arcadia Formation surface
46. Arcadia Formation thickness
47. Nocatee Member of the Arcadia Formation surface
48. Nocatee Member of the Arcadia Formation thickness
49. Tampa Member of the Arcadia Formation surface
50. Tampa Member of the Arcadia Formation thickness
51. Peace River Formation surface
52. Peace River Formation thickness
53. Bone Valley Member of the Peace River Formation surface
54. Bone Valley Member of the Peace River Formation thickness
55. Surficial aquifer system thickness
56. Intermediate aquifer system/intermediate confining unit surface
57. Intermediate aquifer system/intermediate confining unit thickness
58. Floridan aquifer system surface
59. Middle Floridan confining unit surface
BULLETIN NO. 68
Figure 24. Statistical summary of IAS/ICU transmissivity data from Southwest Florida Water
Management District (2006b).
Figure 25. Statistical summary of IAS/ICU storativity data from Southwest Florida Water
Management District (2006b). Asterisks in the box plot denote statistical outliers.
Summary for IAS T (ft^2/day)
0 2000 4000 6000 8000 10000 12000
95% Confidence Intervals
Mean- I I
Median- I I
1000 2000 3000 4000
Anderson-Darling Normality Test
A-Squared 2.66
P-Value < 0.005
Mean 2916.2
StDev 3679.0
Variance 13534930.9
Skewness 1.59693
Kurtosis 1.82144
N 30
M minimum 3.0
1st Quartile 265.5
Median 1186.6
3rd Quartile 4975.1
Maximum 12967.9
95% C confidence Interval for Mean
1542.4 4290.0
95% Confidence Interval for Median
655.4 2874.0
95% Confidence Interval for StDev
2930.0 4945.7
Summary for IAS S
0.0000 0.0004 0.0008 0.0012 0.0016 0.0020 0.0024
95% Confidence Intervals
Mean I S I
Median- I I
0.0001 0.0002 0.0003 0.0004 0.0005 0.0006 0.0007
Anderson-Darling Normality Test
A-Squared 4.03
P-Value < 0.005
Mean 0.000397
StDev 0.000621
Variance 0.000000
Skewness 2.75235
Kurtosis 7.29439
N 25
Minimum 0.000030
1st Quartile 0.000073
Median 0.000180
3rd Quartile 0.000351
Maximum 0.002530
95% Confidence Interval for Mean
0.000141 0.000653
95% Confidence Interval for Median
0.000100 0.000276
95% Confidence Interval for StDev
0.000485 0.000863
ACKNOWLEDGEMENTS
This research was a cooperative effort between the Florida Department of Environmental Protection
(FDEP) Florida Geological Survey (FGS) and the Southwest Florida Water Management District
(SWFWMD). Special thanks are extended to David L. Moore, SWFWMD Executive Director and Dr.
Walter Schmidt, FDEP-FGS Director and State Geologist for administrative and financial support.
Essential geology and hydrogeology data-collection programs in the SWFWMD, FDEP-FGS and the U.S.
Geological Survey (USGS) have made the development of this comprehensive report possible. Numerous
individuals and countless hours of well drilling and logging, aquifer and laboratory testing, database
development and management, lithologic descriptions, formation boundary determinations, surface
modeling, and map/cross section production have contributed to the development of this report.
The authors express their appreciation to the numerous individuals for their insightful review of the
manuscript and plates. From the FDEP-FGS, these individuals include Carol Armstrong, Ken Campbell,
Jackie Lloyd, Frank Rupert, Dr. Walter Schmidt, Dr. Tom Scott; from SWFWMD, Ron Basso, Michael
Beach, Marty Clausen, Michael Gates, Tony Gilboy, Jason LaRoche, John Parker, Robert Peterson and
Donald Thompson. Ken Campbell and Dr. Tom Scott are thanked for their contributions and discussions
regarding the lithostratigraphy and hydrostratigraphy of the study area. Discussions with John J. Hickey,
Rick Spechler, Dr. Tom Scott and Dr. Sam Upchurch helped refine our understanding of the
hydrostratigraphy of the region. Doug Rapphun also contributed to our knowledge of the hydrogeology
in the region.
The authors also gratefully acknowledge those staff of the FDEP-FGS who participated in this project.
Lance Johnson and Paula Polson provided assistance with cross-section development. Surface
interpolations during early phases of the project were completed by Bill Pollock, Amy Graves, John
Marquez and Andrew Rudin. Developers of the database for this project included Mark Groszos, Marco
Cristofari and Rob Stoner. Data management support included the assistance of Jackie Bone, Patricia
Casey, Lance Johnson, Natalie Sudman, and Holly Tulpin. Lithologic descriptions of numerous borehole
samples were completed by Alan Baker, Jim Cichon, Erin Dom, Kris Esterson, Mabry Gaboardi, Diedre
Lloyd, Matt Mayo, Sarah Ramdeen and Holly Williams. Many of the photos and photomicrographs of
fossils presented in this report are provided courtesy of Roger Portell and Sean Roberts (Invertebrate
Paleontology, Florida Museum of Natural History), Dr. Jonathan Bryan (Okaloosa-Walton Community
College) and Frank Rupert. Dr. Rick Copeland was helpful with regard to discussions of quality
assurance of hydrogeologic data and presentation of descriptive statistics.
BULLETIN NO. 68
Metz, P.A., 1995, Hydrogeology and simulated effects of groundwater w ithdida als for citrus irrigation,
Hardee and DeSoto Counties, Florida: U.S. Geological Survey Water-Resources Investigations
Report 93-4158, 83 p.
Meyer, F.W., 1989, Hydrogeology, groundwater movement, and subsurface storage in the Floridan
aquifer system in southern Florida: U.S. Geological Survey Professional Paper 1403-G, 59 p.
Miller, J.A., 1986, Hydrogeologic Framework of the Floridan aquifer system in Florida and in Parts of
Georgia, Alabama and South Carolina: U.S. Geological Survey Professional Paper 1403-B, 91 p.
Geohydrologic data from the Floridan aquifer system in Florida and in parts of Georgia, South
Carolina and Alabama: U.S. Geological Survey Open-File Report 88-86, 387 p.
1997, Chapter 6-Hydrogeology of Florida, in Randazzo, A.F., and Jones, D.D., eds., The
Geology of Florida: Gainesville, University Press of Florida, p. 69-88.
Missimer, T.M., 1993, Stratigraphic relationships of sediment facies within the Tamiami Formation of
southwest Florida: Proposed intraformational correlations, in Scott, T.M., and Allmon, W.D. eds.,
Plio-Pleistocene stratigraphy and paleontology of southern Florida: Florida Geological Survey
Special Publication 36, p. 63-73.
Late Neogene geology of northwestern Lee County, Florida, in Missimer, T.M. and Scott, T.M.,
eds., Geology and hydrogeology of Lee County, Florida: Durward H. Boggess Memorial
Symposium: Florida Geological Survey Special Publication 49, p. 21-34.
2002, Late Oligocene to Pliocene evolution of the central portion of the south Florida platform:
mixing of siliciclastic and carbonate sediments: Florida Geological Survey Bulletin 65, 184 p.
Missimer, T.M., and Gardner, R.A., 1976, High-resolution seismic reflection profiling for mapping
shallow aquifers in Lee County, Florida: U.S. Geological Survey Water-Resources Investigations
76-45, 30 p.
Missimer, T.M, McNeill, D.F., Ginsburg, R.N., Mueller, P.A., Covington, J.M., and Scott, T.M., 1994,
Cenozoic record of global sea level events in the Hawthorn Group and Tamaimi Formation on the
Florida platform: Geological Society of America Abstracts with Programs, v. 26, no. 7, p. A 151.
Missimer, T.M., and Ginsburg, R.N., 1998, Homogenized carbonates and siliciclastics in the Tertiary of
southwest Florida: Gulf Coast Association of Geological Societies Transactions, v. 48, p. 263-
274.
Missimer, T.M., and Martin, W.K., 2001, The hydrogeology of Lee County, in Missimer, T.M., and
Scott, T.M., eds., Geology and hydrogeology of Lee County Florida: Durward H. Boggess
Memorial Symposium: Florida Geological Survey Special Publication 49, p. 91-139.
Missimer, T.M., and Maliva, R.G., 2004, Tectonically induced fracturing, folding and groundwater flow
in south Florida: Gulf Coast Association of Geological Societies Transactions, v. 54, p. 443-459.
Montgomery Watson Americas, Inc., 1997, Charlotte County Utilities West Port wastewater treatment
plant injection well system Injection Well IW-1 and Monitor Well DZMW-1 Drilling and
Testing Report: report prepared for Charlotte County Utilities, unpaginated.
In memory of the spirited life and geoscience
contributions of Rick Lee (1956 2007)
8130'W 81 W
I I
FLORIDAN AQUIFER SYSTEM
SURFACE
0 5 10 20 30 40
,, Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 75 ft
Projection: Custom FDEP Albers
Miles
Gulf
of
Mexico
Explanation
I IStudy Area
z Wells Used
Contours
- Water Management Districts
FAS Surface (ft. MSL)
> 75
-375
S<-825
- --- --
I
I
83W
PLATE 58
I
0
FLORIDA GEOLOGICAL SURVEY
OSCEOLA
-" POOLR
Explanation -
I-] Extent of IAS from Miller (1986)
L I FDEP IAS public supply wells +20km buffer
I _I Approximate extent of permeable IAS/ICU
(present study)
20 10 0 20
Miles
20 10 0 20
Kilometers
Figure 23. Approximate extent of IAS/ICU permeable zones. The region mapped as IAS/ICU
(Plates 56 and 57) north of this line is dominated by lower permeability hydrogeologic facies.
Plate 11. Cross section: H
- H' Pasco and Polk Counties
W-13923 ROMP 85 W-662 ROMP 87
W-14669 W-14889
GAMMA LOG
NO SCALE AVAILABLE
150 -
100 -
50-
0-
--20
- 50-
-100 -
-150 -
-200
-250-
-300-
-350 -
-400 -
-450-
-500 -
-550 -
-600-
-650-
-700-
-750-
-800-
- 40
- 20
20
- 20
- 40
- 60
- -80
--100
- -120
- -140
- -160
- -180
- -200
- -220
- -240
GAMMA LOG
NO SCALE AVAILABLE
I J
PEACE RIVER
EXPLANATION
HATCHING PATTERNS
LIMESTONE
SURFICIAL
AQUIFER
- - SYSTEM
GRAVEL FINE MEDIUM COARSE
DOLOSTONE INTERMEDIATE
D OLOSTONEI AQUIFER SYSTEM/
lvI CONFINING UNIT
FLORIDAN
SAND FINE MEDIUM COARSE AQUIFER
SYSTEM
-- INTERBEDDED LIMESTONE AND DOLOSTONE SS"-- M
SILT FINE MEDIUM COARSE
OCALA
LIMESTONE
AVON PARK
FORMATION
L2 150
GAMMA (CPS)
L
L 100
L
0
50 -
-100 -
-150 -
-200 60
-250 -
-300-
-350-
-400 --120
COMMENTS
MICRfTE
SAND
PHOSPHATE GRAVEL
PHOSPHATE SAND
ORGANIC
SPAR
IRON STAIN
QUARTZ
ANHYDRITE
CHERT
D
L
H
NO SPL
G
Py
SILT
CLAY
SHELL
DOLOSTONE
LIMESTONE
HEAVY MINERALS
NO SAMPLE
GYPSUM
PYRITE
CLAY CHE SHELL BEDAAAAAAAAAAA + GYPSUM +
CLAY CHERT SHELL BED GYPSUM
-450 -
-500-
-550-
-600-
-650
-700 -
-750
-800
-850 -L -260
WEST
H
150 -
- 50
- 40
100 30
50
0-
- 20
10
0
- 50 -10
FEET METERS
TR 16-2A
W-16609
EAST
H'
150
100
o4-
- 50
- 40
- 30
- 20
- 10
0
- -10
ROMP 76
W-14389
- 50
FEET METERS
AVON PARK
FORMATION
AVON PARK
FORMATION
HORIZONTAL SCALE
MILES
0 1 2 3 4 5
0 1 2 3 4 5 6 7 8
KILOMETERS
VERTICAL EXAGGERATION IS APPROXIMATELY
124 TIMES HORIZONTAL SCALE
- 40
- 20
- 0
- 20
- -40
- -80
- -100
- -140
- -160
- -180
- -200
- -220
- -240
- 850 -L -260
BULLETIN NO. 68
and 46). Locations of depocenters within
subjacent lithostratigraphic units occur in
roughly the same locale: the Ocala Limestone,
Suwannee Limestone and Hawthorn Group
deepen in this area (Plates 39, 41 and 43,
respectively), and the units thicken as well
(Plates 40, 42 and 44, respectively). This basin
is also observed in the surface of the Avon Park
Formation (Plate 38); however, due to lack of
well control, Miller's (1986) Middle Eocene
maps do not reflect this feature. These
observations suggest that the area experienced
continued subsidence and infilling from Middle
Eocene through at least Late Miocene.
Alternatively, the apparent depocenters may
have structural control owing to the proximity of
the "North Port" fault (Winston, 1996).
Nocatee Member
The Upper Oligocene (Brewster-Wingard et
al., 1997) Nocatee Member of the Arcadia
Formation is an interbedded sequence of quartz
sands, clays and carbonates all containing
variable amounts of phosphate (Scott, 1988) that
generally average five percent but locally can
reach ten percent or more. The unit is
predominately siliciclastic and generally
interbedded with lower percentages of
carbonate. Original macrofossil material is not
common in this unit; however, fossil molds of
mollusks, algae and corals are observed.
Diatoms are commonly found within the clay
units. Porosity of the Nocatee Member is
generally intergranular, with highly variable
permeability. Total porosity of five core
samples from the Nocatee Member average 27.5
percent (median =24.7 percent) and range from
20.4 percent to 35.4 percent.
The subcrop extent of the Nocatee Member
includes west-central Polk County south to
Charlotte and Glades Counties and extends as
far west as central Sarasota County. The
northeastern limits of the unit are generally well
defined and comprise a stratigraphic pinchout
(e.g., Polk and Highlands Counties); however,
the southwest extent is more subjective as the
unit grades laterally into the undifferentiated
Arcadia Formation, or locally into the Tampa
Member. In an area extending south from
southwestern Polk County, the Nocatee Member
is conformably overlain by the Tampa Member
of the Arcadia Formation. Elsewhere in the
study area, the upper and lower limits of the
Nocatee Member are gradational into the
undifferentiated Arcadia Formation.
The top of the Nocatee Member ranges in
elevation from greater than 50 ft (15.2 m) MSL
in west-central Polk County to depths exceeding
-600 ft (-183 m) MSL in the southeastern part of
the study area (Plate 47). Although the Nocatee
Member ranges in thickness to more than 240 ft
(73.2 m), it averages approximately 75 ft (22.9
m) thick (Plate 48).
Gamma-ray activity within the Nocatee
Member is generally less than or equal to that of
the overlying Hawthorn Group units (i.e., Tampa
Member and Arcadia Formation; e.g., Figure 10
and Plate 26). Where the Nocatee Member is
underlain by (and generally grades into) the
undifferentiated Arcadia Formation, gamma-ray
logs are not as useful in distinguishing between
the two units. On the other hand, where the
Nocatee Member overlies the Suwannee
Limestone, the gamma-ray activity can be very
useful for distinguishing the two units.
Although most of the Nocatee Member
correlates with the IAS/ICU, this
lithostratigraphic unit is hydraulically connected
to the UFA within part of DeSoto County
(Figure 8) and thus locally comprises the
uppermost UFA in those areas.
The Nocatee Member was deposited on the
southeast edge of the carbonate bank prior to
and during deposition of the Tampa Member.
The Nocatee represents a higher energy, more
open near-shore environment and grades
westward into a very sandy facies of the
undifferentiated Arcadia Formation and
northwestward into the carbonate facies of the
Tampa Member (Scott, 1988).
Tampa Member
The Upper Oligocene to Lower Miocene
(Brewster-Wingard et al., 1997) Tampa Member
of the Arcadia Formation is white to yellowish
gray in color and ranges from a wackestone to
BULLETIN NO. 68
Figure 15. Diagnostic foraminifera in Hawthorn Group units. Upper left bar = 0.1 mm; upper
right bar = 1 mm; bottom row, bar = 0.5 mm.
Measured total porosity of 25 Arcadia
Formation samples averages 34.1 percent, with a
median value of 32.4 percent and a range from
12.4 percent to 54.5 percent.
The updip limit of the unit occurs in northern
Pasco and Polk Counties where maximum
elevations exceed 90 ft (27.4 m) MSL (Plate 34
and 45). The top of the Arcadia Formation
occurs at depths exceeding -270 ft (-82.3 m)
MSL beneath the Lake Wales Ridge in the
southeastern part of the study area. The unit
ranges in thickness to greater than 750 ft (229
m) in south-central Charlotte County (Plate 46).
Sporadically throughout much of the central and
southern regions, the Arcadia Formation
(undifferentiated) is observed below the Tampa
and Nocatee Members. In several wells, the
contacts between the Tampa and Nocatee
Members and the underlying Arcadia Formation
(undifferentiated) are gradational. The Arcadia
Formation is unconformably overlain by the
Peace River Formation (where present);
however, apparent gradational contacts between
these two units are locally observed.
In general, the Arcadia Formation comprises
the most permeable parts of the IAS/ICU in the
study area (see IAS/ICU, p. 57, for more details).
In addition, the uppermost part of the FAS is
comprised of the Tampa Member where it is in
hydraulic connection with the subjacent
INTERMEDIATE AQUIFER
SYSTEM / INTERMEDIATE
CONFINING UNIT SURFACE
0 5 10
30 40
Miles
0 510 20 30 40
,= Kilometers
Scale: 1:1,000,000
Contour Interval: 25 ft
Projection:
Custom FDEP Albers
Gulf
of
Mexico
Explanation
W Study Area
Wells Used
I
-- I
-- -
I
r
I--
/
Contours
?I .i Questionable Extent
z Discontinuous*
-,- Approximate northern limit of IAS
permeable zones
- Water Management Districts
IAS / ICU Surface (ft. MSL)
>125
<-200
* Denotes approximate areas where semi-confinement
is laterally more discontinuous than continuous.
Non-hachured areas reflect variable degrees of
confinement that are more laterally continuous.
I I
81 30'W 81'W
PLATE 56
2W 81
0 5
Arcadia Formation
Surface
10 20 30 40
Kilometers
0 510 20 30 40
Scale: 1:1,000,000
Contour Interval: 30 ft
Projection: Custom FDEP Albers
Gulf
of
Mexico
/0 \ 9
0o o \
0 0
Jo
Explanation
S| Study Area
Wells Used
Contours
z - Arcadia Fm. Extents
- Water Management Districts
Arcadia Fm. Surface (ft. MSL)
> 90
- f- -
I
- 1 0- \
P-Iii
0
00 0 0
-90
<-270
PLATE 45
)
Miles
I
4'
--I
~1
0
0
0
a
81 W
I
\
\ 0
0 0
PREFACE
The Florida Geological Survey/Florida Department of Environmental Protection is publishing
as its Bulletin 68, the Hydrogeologic Framework of the Sinhai et Florida Water Management
District. The report summarizes a multi-year study of the three-dimensional framework of
southwestern Florida's hydrogeology, with a focus on the subsurface distribution of aquifer
systems and geologic units comprising these systems. As groundwater resources in Florida
experience increased stress due to rapid population growth, an understanding of the aquifer
systems is invaluable to environmental managers, scientists, planners and the public as decisions
are made regarding use, protection and conservation of these vulnerable resources. The FDEP-
FGS is pleased to have had the opportunity to partner with the Southwest Florida Water
Management District to complete this report.
State Geologist and Director
Florida Geological Survey
Florida Department of Environmental Protection
FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION
Michael W. Sole, Secretary
LAND AND RECREATION
Bob G. Ballard, Deputy Secretary
OFFICE OF THE FLORIDA GEOLOGICAL SURVEY
Walter Schmidt, State Geologist and Director
ADMINISTRATIVE AND GEOLOGICAL DATA MANAGEMENT SECTION
Jacqueline M. Lloyd, Assistant State Geologist
David Arthur, Computer Programmer Analyst
Traci Billingsley, Administrative Assistant
Paulette Bond, Professional Geologist
Doug Calman, Librarian
Brian Clark, Environmental Specialist
Jeff Erb, Systems Programmer
Jessie Hawkins, Custodian
Leslie Knight, Administrative Assistant
Anthony Miller, Environmental Specialist
Sarah Ramdeen, Computer Program Analyst
Ginger Rinkel, Secretary Specialist
Frank Rupert, Professional Geologist
Carolyn Stringer, Management Analyst
GEOLOGICAL INVESTIGATIONS SECTION
Thomas M. Scott, Assistant State Geologist
Ken Campbell, Professional Geologist
Brie Coane, Geologist
Rick Green, Professional Geologist
Eric Harrington, Engineering Technician
Laura Hester, Laboratory Technician
Ron Hoenstine, Professional Geologist Supervisor
Jessie Hurd, Laboratory Technician
Michelle Ladle, Laboratory Technician
Patrick Madden, Laboratory Technician
Harley Means, Professional Geologist
Mike Nash, Laboratory Technician
David Paul, Professional Geologist
Dan Phelps, Professional Geologist
Guy Richardson, Engineering Technician
Wade Stringer, Engineering Specialist
David Wagner, Laboratory Technician
Christopher Williams, Geologist
HYDROGEOLOGY SECTION
Jonathan D. Arthur, Assistant State Geologist (Acting Director)
Rick Copeland, Professional Geologist
Adel Dabous, Environmental Specialist
Rodney DeHan, Senior Research Scientist
Scott Barrett Dyer, Environmental Specialist
Cindy Fischler, Professional Geologist
Lisa Fulton, Environmental Specialist
Tom Greenhalgh, Professional Geologist
Nick John, Geologist
Clint Kromhout, Professional Geologist
Amber Rainsford, Environmental Specialist
BULLETIN NO. 68
Puri, H.S., and Winston, G.O., 1974, Geologic framework of the high transmissivity zones in south
Florida: Florida Geological Survey Special Publication 20, 101 p.
Randazzo, A.F., 1997, Chapter 4 The sedimentary platform of Florida: Mesozoic to Cenozoic, in
Randazzo, A.F., and Jones, D.D., eds., The Geology of Florida: Gainesville, University Press of
Florida, p. 39-56.
Randazzo, A.F., and Hickey E.W., 1978, Dolomitization in the Floridan aquifer: American Journal of
Science, v. 278, p. 1177-1184.
Randazzo, A.F., and Zachos, L.G., 1984, Classification and description of dolomite fabrics of rocks from
the Floridan aquifer, USA: Sedimentary Geology, v. 37, p. 151-162.
Randazzo, A.F., Kosters, M., Jones, D.S., and Portell, R.W., 1990, Paleoecology of shallow-marine
carbonate environments, Middle Eocene of peninsula Florida: Sedimentary Geology, v. 66: p. 1-
11.
Renken, R.A., 1998, Groundwater atlas of the United States: Segment 5, Arkansas, Louisiana,
Mississippi: U.S. Geological Survey Hydrologic Atlas 730-F, 28 p.
Reese, R.S., 2000, Hydrogeology and the distribution of salinity in the Floridan aquifer system,
southwestern Florida: U.S. Geological Survey Water-Resources Investigations Report 98-4253,
86 p.
Reese, R.S. and Richardson, E., 2008, Synthesis of the hydrogeologic framework of the Floridan aquifer
system and delineation of a major Avon Park permeable zone in central and southern Florida:
U.S. Geological Survey Scientific Investigations Report 2007-5207, 60 p.
Riggs, S.R., 1979a, Phosphorite sedimentation in Florida a model phosphogenic system: Economic
Geology, v. 74, p. 285-314.
1979b, Petrology of the Tertiary phosphorite system of Florida: Economic Geology, v. 74, p.
195-220.
1984, Paleoceanographic model of Neogene phosphorite deposition, US Atlantic continental
margin: Science, v. 223, no. 4632, p. 123-131.
Rupert, F.R., 1989, Selected Cenozoic benthic foraminifera from Florida: Florida Geological Survey
Poster 2.
Rupert, F., and Arthur, J.D., 1990, The geology and geomorphology of Florida's coastal marshes: Florida
Geological Survey Open-File Report 34, 13 p.
Ryder, P.D., 1982, Digital model of redevelopment flow in the Tertiary limestone (Floridan) aquifer
system in west-central Florida: U.S. Geological Survey Water-Resources Investigations Report
81-54, 61 p.
Ryder, P.D., 1985, Hydrology of the Floridan aquifer system in west-central Florida: U.S. Geological
Survey Professional Paper 1403-F, 63 p.
BULLETIN NO. 68
Figure 28. Statistical summary of IAS/ICU vertical hydraulic conductivity data based on falling-
head permeameter analyses of core samples completed at the FDEP-FGS. Asterisks in the box plot
denote statistical outliers.
Figure 29. Statistical summary of IAS/ICU total porosity data based on core sample volumetric
analyses completed at the FDEP-FGS.
Summary for IAS Kv (ft/day)
0.0035 0.0110 0.0185 0.0260 0.0335
95% Confidence Intervals
Mean- I S I
Median I-I ------I
0.000 0.001 0.002 0.003 0.004 0.005 0.006
Anderson-Darling Normality Test
A-Squared 6.72
P-Value < 0.005
Mean 0.003318
StDev 0.006677
Variance 0.000045
Skewness 2.69316
Kurtosis 7.41148
N 38
Minimum 0.000000
1st Quartile 0.000048
Median 0.000337
3rd Q uartile 0.003100
Maximum 0.030300
95% Confidence Interval for Mean
0.001124 0.005513
95% Confidence Interval for Median
0.000102 0.001230
95% Confidence Interval for StDev
0.005443 0.008638
Summary for IAS Total Porosity (% )
A
15.0 22.5 30.0 37.5 45.0 52.5
95
95
95% Confidence Intervals
Mean- I 9 I 95
Median- I S I
30 32 34 36 38 40
, nderson-Darling Normality Test
A-Squared 0.34
P-Value 0.447
Mean 34.126
StDev 9.540
Variance 91.010
Skew ness -0.547647
Kurtosis 0.466245
N 19
Minimum 14.130
1st Q uartile 28.900
Median 35.370
3rd Quartile 39.400
Maximum 49.550
0% Confidence Interval for Mean
29.528 38.724
% Confidence Interval for Median
29.626 38.225
% Confidence Interval for StDev
7.208 14.108
TABLE OF CONTENTS
A bbreviations, acronym s and conversions. ......................................................................... ................. xi
A know ledgem ents .......................................................................................................... ............. . xii
Introduction ............................................................................... 1
Background .............................................................................. 1
P u rp o se an d sco p e ................................................................................................................................. 1
Study area ..................................................................................................... ................ 2
Previous investigations ........................................ .. ........... .............................. 2
P h y sic al setting g ............................................................................................................... ...................... 5
Geology .................................................................... ..................... 5
S tru ctu re ...................................................................................................................... ..................... 7
G eom orph ology ................. ................................................................................................ ........... 11
Physiographic provinces and features........................................... ............................................ 11
Sinkholes ............................................................................................. ...... ............... 15
S p rin g s .................................................................................................................. ..................... 15
H y d ro g eo lo g y ........................................................................................................... ..................... 17
M methods ............................................................................................... 20
S am p le description ................................................................................................................. . ........... 2 0
D elin nation of b oun diaries ............................................................................ ..................................... 2 1
Formations/Members ........................................ .. ........... .............................. 21
A qu ifer sy stem s ....................................................................................... ......... .......... ......... .. 2 1
C ro ss-section con struction ............................................................................ .................................... 22
T o p o g rap h y ............................................................................................................... ...................... 2 2
L ith o lo g y ................................................................................................................. ...................... 2 4
G am m a-ray logs ..................................... ........................................................... ................ 24
A quifer system s .................................................................................... .................... 24
M ap develop ent and data m anagem ent............................................. .......................... ................. 24
M ap interpolation and spatial accuracy ........................................... .......................... ................ 27
C ontour interval selection .......................................................... ................................................... 30
S tratig rap h y ...................................................................................................................... ...................... 3 0
L ithostratigraphy ...................................... ............................................................ ............. . 30
Introduction ................................................................................................................ 30
E ocene Series ........................................................................................................... 30
Oldsmar Formation .............................................. .. ........... .............................. 30
A von Park Form action .................. .................... ........... ...... ................. .. 31
O cala L im stone .................................... ................................................................ . ......... .. 34
O ligocene Series .............................................................................................................. . .......... 37
Suwannee Limestone .................................... .. ............ .......................... .. 37
O ligocene-P liocene Series ............... ........................................................................... 40
H aw thorn G group .................................... ................................................................ . ........... 40
Arcadia Formation ......................................... .. ............ .......................... .... 40
Nocatee Member ............................... .. ............ .............................. .. 43
Tampa Member .................................. .. ............ .............................. .. 43
"V enice Clay" ........................ .. ............................. ........ .......... ................ 45
P eace R iv er F orm action .............................................................................. ...... ................ 4 5
B on e V alley M em b er ............................................................................. ...... ................ 4 8
FLORIDA GEOLOGICAL SURVEY
Figure 36. Statistical summary of UFA horizontal hydraulic conductivity data from Southwest
Florida Water Management District (2006b). ** calculated from transmissivity and permeable
zone thickness. Asterisks in the box plot denote statistical outliers.
Summary for UFA Kv* (ft/day)
Anderson-Darling Normality Test
A-Squared 26.02
P-Value < 0.005
Mean 0.10028
StDev 0.22808
Variance 0.05202
Skewness 4.2139
Kurtosis 21.8401
N 137
M inim um 0.00000
0.0 0.3 0.6 0.9 1.2 1.5 1st Q uartile 0.00565
SMedian 0.01967
3rd Q uartile 0.08725
t* * t * Maximum 1.72957
95% C confidence Interval for Mean
0.06175 0.13882
95% Confidence Intervals 95% Confidence Interval for Median
I _0.01422 0.02795
Mean 95% Confidence Interval for StDev
Median 0.20389 0.25882
0.000 0.025 0.050 0.075 0.100 0.125 0.150
Figure 37. Statistical summary of UFA vertical hydraulic conductivity data based on results of
falling-head permeameter analyses of core samples completed at the FDEP-FGS. Asterisks in the
box plot denote statistical outliers.
Summary for UFA Kh** (ft/day)
0 1000 2000 3000 4000 5000 6000
j*- ** 9
9!
95% Confidence Intervals 95
Mean- I 9
Median- F-
100 200 300 400 500
Anderson-Darling Normality Test
A-Squared 21.43
P-Value < 0.005
Mean 276.61
StDev 787.65
Variance 620386.37
S kew ness 5.8896
Kurtosis 38.2409
N 86
M inim urn 7.65
1st Q uartile 50.50
Median 91.90
3rd Q uartile 178.75
Maxim umrn 6050.00
5% Confidence Interval for Mean
107.74 445.49
% Confidence Interval for Median
78.51 110.07
5% Confidence Interval for StDev
684.97 926.82
BULLETIN NO. 68
communication). It is likely that this factor has
biased identification of mudstones in lithologic
descriptions that may technically be fine-grained
grainstones.
During archiving of borehole cuttings,
samples are gently washed in a 63 micron sieve
to remove any drilling mud (e.g., silt and clay-
sized material). When describing lithologic
characteristics of borehole cuttings, care was
taken to inspect the washed and unwashed
archival fractions of the samples. In many
cases, especially for older wells, the washed
sample fraction may under-represent the clay
fraction of the sample. For example, cuttings
representing the sandy clayey Nocatee Member
(Arcadia Formation) may have been washed to
the degree that only sand remains in the archived
sample. In such cases, the unwashed sets of
samples provide a better representation of the
original clay-rich lithology.
The descriptions are coded within the
aforementioned Microsoft AccessTM database -
FGS Wells. This database is undergoing
continued enhancements including migration to
a more robust enterprise-level platform. These
and other lithologic descriptions are available
from the Florida Geological Survey web site:
http: //www.dep.statefl.us geology/.
Delineation of Boundaries
Formations/Members
Formation and member boundaries were
determined for all described samples and for
cores, cuttings and geophysical logs from an
additional -600 wells. Florida Geological
Survey published and unpublished data (e.g.,
Stewart, 1966; Hickey, 1982, 1990; Johnson,
1986; Miller, 1988; Scott, 1988; Campbell,
1989; DeWitt, 1990; Campbell et al., 1993,
1995; Clayton, 1994, 1999; Green et al., 1995,
1999; Sacks, 1996; Arthur et al., 2001a; Gates,
2001; Missimer, 2002; and O'Reilly et al., 2002)
provided lithostratigraphic and hydrostratigraphic
boundary information on an additional -200
wells. Gamma-ray logs and fossil assemblages
are used only to supplement the lithologic data
in the determination of the boundaries. Where
uncertainty exists regarding the exact position of
the formation boundary, or where the boundary
is inferred within an interval of poor or no
sample recovery, a dashed rather than solid line
is shown on the cross sections. Dashed contacts
are also drawn where only a gamma-ray log was
used and no samples were available for
inspection. In cases where sample quality is
poor, as is often true with cuttings, the gamma-
ray logs become more important in the
determination of formation boundaries.
Uncertainties in lithostratigraphic unit
boundaries were recorded in a database of
elevations and thicknesses. These uncertainties
exist for several reasons. In the case of
inspecting cores, it is not uncommon for two
experienced geologists to disagree on a
formation boundary, especially when it is subtle
or gradational. Moreover, the core may have
poor recovery, resulting in missing intervals.
Regarding cuttings, samples often contain
borehole cavings, whereby the sampled interval
contains sediment or rock fragments from
overlying units. For example, in an extreme
case, dolostone cuttings from the Avon Park
Formation may contain phosphatic sands from
the upper Hawthorn Group. As a result, it is not
uncommon for a formation boundary estimation
based on cuttings to include an uncertainty range
on the order of 20 ft (6.1 m) based solely on
sample quality. Other uncertainties with respect
to mapped unit elevations also exist (see Map
Development and Data Management, p. 24).
Table 2 summarizes the lithostratigraphic
units shown on the maps. The same units are
also shown on the cross sections. For the
purposes of this study, post-Hawthorn units are
depicted as Pliocene-Pleistocene sediments
(undifferentiated) and Pleistocene Holocene
undifferentiated sand and shell or sand and clay
(UDSS or UDSC, respectively).
Aquifer Systems
Delineations of hydrostratigraphic units in
this report are based on the following: 1)
available hydrogeologic data collected during
drilling, 2) borehole geophysical logs,
BULLETIN NO. 68
Similar to basal Peace River Formation lag
deposits, reworked Miocene-Pliocene sediments
may also yield a phosphate lag deposit at the
base of overlying (e.g., post-Hawthorn Group)
sediments. Units superjacent to the Peace River
Formation include the Tamiami, Ft. Thompson
and Caloosahatchee Formations. In most cases,
the Peace River Formation is readily
distinguished from these overlying
sand/shell/carbonate lithofacies.
Lateral facies transitions of the Peace River
Formation are most evident along the
northwestern extent of the unit in Hillsborough
and Polk Counties (Plate 51). In this area,
sediments characteristic of the Peace River
Formation grade into clay-rich and phosphate-
poor sediments of the undifferentiated Hawthorn
Group (e.g., Plate 13).
Maximum elevations of the Peace River
Formation occur in the vicinity of the Polk
Upland and Lakeland Ridge, where the unit
exceeds 125 ft (38.1 m) MSL (Plate 51). The
maximum observed depth of the Peace River
Formation exceeds -200 ft (-60.9 m) MSL along
the Lake Wales Ridge. Thicknesses range to
over 120 ft (36.6 m) along the southeastern third
of the unit's mapped extent (Plate 52).
Gamma-ray activity in the Peace River
Formation is highly variable. In some areas, due
to the high-phosphorite content in the sediments,
strong gamma-ray peaks are readily observed in
contrast to lower gamma-ray activity of the
Arcadia Formation (e.g., W-16576 [ROMP DV-
1], Plate 33). The opposite occurs as well,
where gamma-ray activity in the Peace River
Formation is lower than that of the Arcadia
Formation (Figure 10). Where the Peace River
Formation lies above Eocene carbonates, the
difference is also pronounced, with the younger
unit exhibiting a stronger gamma-ray signal
(Plate 20). In many wells, a lack of gamma-ray
contrast between the Peace River Formation and
the Arcadia Formation is observed (W-16740
[ROMP 39], Plate 33). In wells where the base
of Peace River Formation contains a reworked
phosphate lag deposit, a characteristically strong
gamma-ray peak is observed (e.g., W-15938,
Plate 22). The unit may also be overlain by a
similar lag deposit within undifferentiated post-
Hawthorn Group sediments.
The Peace River Formation is a regional
confining to semi-confining lithostratigraphic
unit within the upper part of the IAS/ICU.
North of central Hillsborough and Polk
Counties, the Peace River Formation and
undifferentiated Hawthorn Group sediments
comprise a low-permeability confining to semi-
confining facies of the IAS/ICU. South of this
region, permeable, water-producing zones exist
within interlayered carbonate lenses (e.g., Ryder,
1985, Torres et al., 2001). In some areas, the
uppermost sediments of the Peace River
Formation are in hydraulic connection with
overlying sands due to a low-to-absent clay
content (e.g., Plate 17, W-14382 [ROMP 23]).
As a result, the Peace River Formation may
comprise the lower part of the SAS. Clay-poor
sediments occur within the uppermost Peace
River Formation in eastern Sarasota County and
western Manatee County (Tom Scott, personal
communication, 2006).
The Middle Miocene Lower Pliocene Peace
River Formation sediments characterize a
complex depositional environment strongly
influenced by sea-level fluctuations (Missimer et
al., 1994). The northern extent of the unit was
deposited in a shallow marine, deltaic to
brackish water environment while further south
open marine conditions prevailed (Scott, 1988).
Carbonate deposition in the unit was
periodically restricted by a flood of siliciclastics
from the north and a rise in sea level (Scott,
1988). Missimer (2001) suggests that the Peace
River Formation immediately south of the study
area was deposited in a variety of depositional
environments ranging from inner ramp to deltaic
to beach and can be explained by shoaling
upward or lateral accretion of sediment. Sea-
level transgressions or highstands appear to
favor phosphogenesis, while reworking of the
sediments during sea-level regressions or
lowstands concentrate the phosphorite (Compton
et al., 1993). Phosphorite concentrations are
considered economic ore deposits in the central
region and are locally mined.
BULLETIN NO. 68
"Venice Clay"
The Venice Clay is an informal unit
originally considered part of the lower Tamiami
Formation (Pliocene); however, microfossil data
suggest an age of Early to Middle Miocene
(Scott, 1993). Scott (1992b) suggests informal
placement of the Venice Clay in the upper half
of the Arcadia Formation based on subjacent and
suprajacent lithologies and preliminary fossil
evidence. The Venice Clay is gray-green
magnesium-rich clay, variably dolomitic with
minor amounts of quartz sand and silt. The unit
rarely contains phosphorite and becomes
increasingly silty toward its upper and lower
contacts (Campbell et al., 1993).
The subcrop extent of the Venice Clay
includes Sarasota County and adjacent parts of
Manatee, DeSoto and Charlotte Counties; the
unit may also extend offshore (Barr, 1996).
Based on data collected in the present study, the
top of the unit generally occurs between -10 ft
MSL and -100 ft MSL (-3.1 to -30.5 m). Barr
(1996) reports that thickness of the unit ranges
up to approximately 30 ft (9.1 m). Gamma-ray
activity is diagnostically very low for this unit,
(note clay beds near top of the Arcadia
Formation in W-15683 [TR 3-3]; Plate 19),
suggesting the mineral assemblage does not
include abundant potassium-rich illite-group
clays. The Venice Clay was likely deposited in
a quiet shallow water marine environment -
possibly an estuary (Tom Scott, personal
communication, 2004).
The Venice Clay acts as a confining unit in
the upper part of the IAS/ICU. Specifically,
Barr (1996) suggests that it comprises the
confining unit below "permeable zone 1."
Owing to its limited thickness and aerial extent,
as well as recent mapping by Barr (1996), the
Venice Clay is not mapped in the present study.
Peace River Formation
The Middle Miocene to Lower Pliocene
(Scott, 1988; Covington, 1993) Peace River
Formation is comprised of yellowish gray to
olive gray, interbedded sands, clays and
carbonates with the siliciclastic component
being dominant (Scott, 1988). The relative
abundance of carbonate beds generally increases
toward the south, especially near the base of the
unit. Variable amounts of phosphate sand and
gravel are interspersed throughout the unit;
however, they are most common within the
uppermost beds. The Peace River Formation
contains a diverse fossil assemblage of marine
and terrestrial fauna (e.g., shark teeth and
vertebrae, ray spines, horse teeth, dugong and
whale ribs, etc.), especially within the Bone
Valley Member (Figure 16). Porosity types in
the formation are generally intergranular, except
in the carbonate-rich zones, where moldic
porosity is also present. Only two total porosity
analyses of Peace River Formation samples have
been measured in this study. The results, 34.4
percent and 39.4 percent, should not be taken as
representative of the unit given its diverse
lithology.
Lithologic characteristics of the Peace River
Formation are generally consistent; however, the
carbonate component becomes more prevalent
from north to south as the unit thickens.
Throughout most of its extent, the Peace River
Formation does not contain shell material, with
possible exception of southeast DeSoto County,
where barnacles are present within the unit
(Green et al., 1999). These barnacle-rich
sediments may be the equivalent of "unit 11"
from Petuch (1982). Missimer (2001) reports
shell material in the Peace River Formation
south of Charlotte County. In the same region,
calcareous nannofossils occur in the unit
(Covington, 1993).
The Peace River Formation generally has an
unconformable contact with the underlying
Arcadia Formation. In an isolated area in north-
east-central Hillsborough County, the Peace
River Formation directly overlies the Tampa
Member (Plates 13 and 33). The Peace River
Formation also has an unconformable contact
with the underlying Ocala Limestone in northern
Polk County (Plates 11 and 34; W-14389
[ROMP 76]). In this area, reworked Peace River
Formation sediments may occur unconformably
above the Avon Park Formation where the Ocala
FLORIDA GEOLOGICAL SURVEY
Another option is to consider the IAS as a complex system of nearly statewide extent, recognizing that
aquifers within this predominantly confining/semi-confining system are sub-regional to regional, yet the
overall correlative hydrostratigraphic package is unique relative to the surficial and Floridan aquifer
systems. Along this line of reasoning, one may consider the confining/semi-confining sediments in the
northern part of the study area as a low-permeability hydrogeologic facies of the IAS. It is noteworthy
that hydraulic characteristics of semi-confining zones identified in Florida are considered "aquifers" or
"permeable zones" in other parts of the country, thus lending support to the statewide IAS concept. Fetter
(2001) describes an aquifer as a "geologic unit that can store and transmit water at rates fast enough to
supply reasonable amounts to wells. The intrinsic permeability of aquifers would range from about 10-2
darcy upward." Albeit subjective, clayey sands often considered part of semi-confining (and
"confining?") units in Florida fall within Fetter's (2001) aquifer definition.
The proposal of a statewide IAS, however, may lead to perception issues for the lay public as well as
concerns regarding aquifer-system definitions. Many geoscientists contend that statewide use of the IAS
name is inconsistent with existing aquifer-system definitions. Moreover, use of the IAS name in the
northern study area may incorrectly imply to the non-scientist that significant water-yielding
"intermediate" strata exist in the region, which is not the case.
BULLETIN NO. 68
Upper Floridan aquifer
Thickness
0 5 10 20 30 40
~m 3= Miles
0 510 20 30 40
Kilometers
Scale 1:1,750,000
Contour Interval: 150 ft
Projection: Custom FDEP Albers
Explanation
m |Study Area
Contours
- Water Management Districts
UFA Thickness
I 1600 ft
665 ft
265 ft
Figure 32. Thickness of the Upper Floridan aquifer (includes non-potable).
Gulf
of
Mexico
BULLETIN NO. 68
faults in the Suwannee Limestone exists to some
degree within two areas. The feature most
supported by the data presented herein is an
inferred northwest-striking fault in northwestern
Polk County (Figure 3). The Suwannee
Limestone thickness map (Plate 42) indicates an
abrupt change in thickness; wells reflecting
more than 100 ft (30.5 m) of the unit are
proximal to wells that contain no Suwannee
Limestone even though the wells are deep
enough to have encountered the unit (assuming
similar regional dip). The strike and polarity of
this particular feature, indicated as an inferred
fault on Plate 41 and 42, roughly agrees with a
fault proposed by Pride et al. (1966). Northeast
of the fault, the Suwannee Limestone is reported
to occur as exposed remnant boulders in Sumter
County (Campbell, 1989).
A second inferred fault may occur along the
updip limit of the Suwannee Limestone in
northeastern Hernando County (Figure 3).
Vernon (1951) reports a fault intersecting the
"Inglis Member" in the area, with the upthrown
side to the northeast. Data represented in Plates
41 and 42 support the location and polarity of
Vernon's (1951) fault for the Suwannee
Limestone. Thicknesses greater than 50 ft (15.2
m) terminate along the northeastern subcrop
limit of the unit (Plate 41 and 42). In the
Charlotte Harbor area, the "North Port" fault
(Winston, 1996) may have affected the
Suwannee Limestone surface and thickness,
similar to that of the Ocala Limestone and Avon
Park Formation. Other faults and lineaments are
reported in this area (Hutchinson, 1991;
Winston, 1996; Michael Fies, personal
communication, 2007) suggesting a complex
geologic setting.
The Suwannee Limestone is characterized by
a gamma-ray log response (i.e., activity) that is
generally more variable within the lower half of
the unit (e.g., Plate 11 and 12; Figure 10).
Relative to the Ocala Limestone, it has an
overall higher background rate and exhibits
much more variability. This variability is likely
due to higher amounts of dolomite, organic
material and other non-calcitic constituents in
the Suwannee Limestone relative to the Ocala
Limestone. Although the gamma-ray log is
generally useful for providing corroborative
evidence for the lithostratigraphic boundary
between the Eocene Oligocene carbonates, use
of the logs for determination of the upper
boundary of the Suwannee Limestone is not
always as straightforward. For example, where
the Tampa Member (Arcadia Formation) is in
contact with the Suwannee Limestone, gamma-
ray signatures for the two units are quite similar,
both in their background count rates and
distribution of peaks (e.g., Plate 31, W-15204
[TR14-2] and Plate 33, W-16740 [ROMP 39]).
A generally consistent pattern in the
Suwannee Limestone gamma-ray logs,
especially for wells in Gulf-coastal counties, is
the presence of a 50- to 100-ft (15.2 to 30.5 m)
thick interval of high gamma-ray activity within
the central to lower parts of the Suwannee
Limestone. This interval varies in thickness and
depth and apparently does not correlate with a
given stratigraphic horizon. Inspection of
lithologic logs suggests that this high gamma-
ray activity zone is associated with dolomite
and/or minor organic content.
The Suwannee Limestone, where present,
comprises most of the FAS surface; exceptions
being where hydraulic continuity exists between
the Tampa Member (Arcadia Formation) and
Suwannee Limestone in Pasco, Pinellas, most of
Hillsborough and northern Manatee Counties
(Figure 8). Along the updip limit of the Tampa
Member in Pasco County, the top of the FAS
includes the Tampa Member (where present)
and the Suwannee Limestone (Figure 8).
Grainstones within the Suwannee Limestone are
among the most permeable zones in the UFA.
Suwannee Limestone deposition occurred in
shallow open marine to peritidal environments
on the Florida Platform (Cander, 1994) until the
Late Oligocene sea-level low stand (Hammes,
1992). During deposition of the unit in the study
area, the Georgia Channel System (Huddlestun,
1993) acted as a barrier to a southward influx of
plastic sediments from the Appalachian
Mountains. Deposition of the predominantly
skeletal lithologies was cyclic and controlled by
the pre-existing topography as well as
fluctuating sea level. Restricted marine facies
and skeletal shoal facies developed on previous
highs and deeper subtidal facies occurred in the
lows. Hammes (1992) describes the Suwannee
Plate 8. Cross section: E E' Hernando, Sumter, and Lake Counties
R17EIR18E R18EIR19E R19EIR20E
w^
(E)
100
50-
0-
- 50-
-100 -
-150 -
-200-
-250-
-300-
-400-
-450-
-500-
-550-
EAST
,E'
R23E R24E
R21EIR22E
225 70
200 60
275 -
80
250-
225 - 70
200 60
175-
50
150-
125-- 40
100- 30
75 -
20
50
10
25
0 -- 0
25- 10
FEET METERS
150 -1
ROMP 105 W-4205 W-15942 ROMP 102
W-15681 W-50096
0 50 100 0 2 50
I 1 0 0 25 50 75
HORIZONTAL SCALE
MILES
0 1 2 3 4 5
liII I Ii iI i I
0 1 2 3 4 5 6 7 8
KILOMETERS
fVER1ICAL EXAGGERATION IS APPROXIMATELY
E E 135 TIMES HORIZONTAL SCALE
,'SURCIAL
GRAVEL FINE MEDIUM COARSE
DOL INTERMEDIATE
.OLOSTONE AUIFER SYSTEM/
CONFINING UNIT
SAND FINE MEDIUM COARSE FLAQUIFER
..... ........ .. SYSTEM
MICRITE T
SAND C
PHOSPHATE GRAVEL Sh
PHOSPHATE SAND D
ORGANIC L
SPAR H
IRON STAIN NO SPL
QUARIZ G
ANHYDRITE Py
CHERT
175
150
125-
100
75 -
50-
25 -
0
- 25
FEET
W-12794
150 -
50
40
30
20
10
0
10
METERS
40
20
- 40
-200 60
-250 -
-300 -
-350 -
-400-
-450-
-500 -
-550 -
-600 -
> THIN MANTLE OF IAS/ICU SEDIMENTS
* CONTACT IS DASHED BASED ON INSPECTION OF DRILLER'S LOG
a.aa........
I--AA.I....aaa....
CLAY CHERT
SHELL BED GYPSUM
i7
- 650 -200
\--200
--240
- 800 -
WEST
E
TR 19-3
W-14873
WITHLACOOCHEE
RIVER
SILT
CLAY
SHELL
DOLOSTONE
UMESTONE
HEAVY MINERALS
NO SAMPLE
GYPSUM
PYRITE
-600 -
-650 t -200
- -220
-240
0 +
-800 -
Table 3. Summary of krige interpolation statistics for each map; ASE is average standard error of the prediction error; RMS is root mean
square of the prediction error. Gray pattern indicates that the prediction error may be overestimated (i.e., ASE>RMS).
Map Unit Prediction error (1s)J Prediction error (1s; map)4 Map "Grid to Point" Number Model
(s)=surface ASE RMS Mean of the 2 X Mean of Contour Error Calculation of Wells5 Algorithm
(t)=thickness ASE (1s) the ASE (2s) Interval
_________________ mean s________
Hawthorn Group (s) 23 34 22 44 25 1.64 11 526 Exponential
Hawthorn Group (t) 57 68 56 112 75 -0.25 21 321 Spherical
Peace River (s) 25 35 22 44 25 0.64 9 349 Exponential
Peace River (t) 27 34 37 74 30 0.33 25 324 Exponential
Bone Valley Mbr. (s) 26 35 23 46 40 2.61 10 33 Exponential
Bone Valley Mbr. (t) 7 7 10 20 20 0.26 3 38 Spherical
Arcadia Fm. (s) 29 35 25 50 30 0.7 11 466 Exponential
Arcadia Fm. (t) 61 122 75 -0.27 19 341 Exponential
Tampa Member (s) 44 88 50 0.6 11 235 Exponential
Tampa Member (t) 40 40 39 78 50 0.13 30 190 Exponential
Nocatee Member (s) 55 110 75 1.11 12 117 Exponential
Nocatee Member (t) 37 74 50 -0.24 21 105 Exponential
Suwannee Limestone (s) 68 136 75 0.98 18 414 Exponential
Suwannee Limestone (t) 43 47 37 74 50 0.1 12 265 Exponential
Ocala Limestone (s) 63 126 75 0.97 14 527 Spherical
Ocala Limestone (t) 34 49 30 60 50 -0.15 10 325 Exponential
Avon Park Fm. (s) 79 158 100 0.77 13 391 Circular
SAS (t) 25 29 25 50 25 0.41 18 703 Exponential
IA.C/II I ( 94 AA 91 A4 25r -1 27 1 41RR Fvnnnential
IAS/ICU (t)
FAS (s)
MFCU (s)
54 108 75 0.02 18 334 Spherical
64 128 75 0.87 16 655 Exponential
167 334 150 0.83 12 101 Spherical
3 krige statistics based on rectangular fit around distribution of wells
4 krige statistics based on irregular extent of mapped unit, which more accurately represents error within the study area
5 total number of wells used to produce each map, including wells (not shown on plates) within the outer 10 mile buffer zone
.
FLORIDA GEOLOGICAL SURVEY
of the inferred "offsets" in his study are due to
wells having encountered buried karst pinnacles
and paleo-sinks. Carr and Alverson (1959),
Pride et al. (1966), and Vernon (1951) report a
northwest trending normal fault(s) in
northwestern Polk County (fault group "FG-1",
Figure 3). Pride et al. (1966) suggest that the
fault affects not only the Avon Park Formation,
but also juxtaposes the Suwannee Limestone and
Ocala Limestone. Carr and Alverson (1959)
indicate that the fault penetrates Hawthorn
Group sediments as well. Both studies report
the northeast block of the inferred fault as the
upthrown side. In the present study, evidence
supports two possible northwest-trending faults
along the northeastern extent of the Suwannee
Limestone (Figure 3; see also Suwannee
Limestone, p. 37). Both faults are similar in
strike and offset direction (polarity) to fault
group "FG-1" in Figure 3. One of the offsets
proposed herein is a northwestern extension of a
fault proposed by Carr and Alverson (1959).
Faults affecting Middle and Upper Eocene
(e.g., Avon Park Formation and Ocala
Limestone) strata are proposed along the Polk-
Osceola County boundary (Pride et al., 1966;
Miller, 1986). The Kissimmee Faulted Flexure
(Vernon, 1951; "E" in Figure 3) occurs in the
same area and was originally considered a
wedge-shaped, fault-bounded block that had
been tilted and rotated, with beds containing
small folds and structural irregularities. Wells
that penetrate the feature contain variably thick
Pliocene-Miocene sediments that overly the
Avon Park Formation. Scott (1988) and Davis
et al., (2001) consider the Kissimmee Faulted
Flexure to be an Avon Park Formation
stratigraphic high with the Ocala Limestone and
Hawthorn Group sediments locally absent due to
erosion. Additional faults ("FG-2" in Figure 3)
affecting the subcrop extent of the Ocala
Limestone along the western margin of the
Flexure have also been proposed. Data
presented in this study support the
interpretations of Scott (1988) and Davis et al.,
(2001).
Further to the south in the vicinity of
Charlotte Harbor, a west-northwest trending
reverse fault penetrating a dolostone layer in the
Suwannee Limestone is proposed (Hutchinson,
1991). Maps presented herein do not lend
support to the inferred reverse fault. In the same
area, a series of northeast-trending lineaments
along the northern margin of Charlotte Harbor
(Michael Fies, personal communication, 2007)
coincide with anomalously high groundwater
temperatures in the upper FAS (Smith and
Griffin, 1977) suggesting a potential line of
further investigation (E. Richardson, written
communication, May, 2006). The "North Port
Fault" (Winston, 1996) strikes nearly coast-
parallel (northwest) across North Port and Punta
Gorda. Winston (1996) suggests that the
downthrown side may occur on the southwest
block, which more or less coincides with
thickening and deepening of several units
mapped in the present study (see
Il,,i,,ibvs,,!hy, p. 30, for further discussion).
South of the study area, west-northwest trending
normal and reverse faults offsetting Miocene
Hawthorn Group sediments on the order of 50 to
100 ft (15 to 30.5 m; vertical) are reported
(Sproul et al., 1972).
Evidence of some degree of vertical offset is
present within cores in the study area; however,
there is insufficient proximal well control to
delineate faulting. Core from W-16913 (ROMP
5), for example, contains abundant high-angle
fractures and slickensides that make some
lithostratigraphic unit surfaces obscure.
Regarding hydrostratigraphic units, brecciated
and fractured zones in core from W-17392
(ROMP 13) contribute to difficulties correlating
the Middle Floridan confining unit. These are
only two of many examples of fractured
intervals encountered during data collection that
warrant further structural study.
Small irregular surfaces in Miocene and older
lithostratigraphic units in the southern part of the
study area raise many questions regarding the
prevalence of structural deformation within
Florida's relatively young carbonate platform.
Missimer and Maliva (2004) suggest that
observed disturbances in lithostratigraphic
surfaces throughout Florida are due to
"differential subsidence by tensional basement
displacement." Their conclusions are based on
seismic surveys and borehole data attained from
areas of variable formation depths. Charlotte
and Lee Counties are among the most widely
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