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., expect more quakes
Early this month, an earthquake
rocked the Virgin Islands. The
recovery from Hurricane Marilyn is
not yet over for many island resi-
dents, especially on St. Thomas.
But here we were, the earth rum-
bling under our feet from an earth.
quake measuring 4.7 on the Richter
scale.
Believe me. nobody wants
another natural disaster.
Earthquakes are a natural part of
man's environment, and no part of
the world can claim to be complete-
ly immune from them.
Seismology is the study of earth-
quake causes, their occurrences,
and their properties. Seismology
also makes use of seismic waves to
study the interior of the earth, assist
in oil and mineral exploration, and
to detect secret underground nucle-
ar explosions in distant places.
The history of earthquakes also
runs deep in cultures and the writ-
ings of people before us. In ancient
Olasee
Davis
Ou
rnmulrnt
Japanese folklore, "a great catfish
lay beneath the ground and pro-
duced earthquakes by thrashing Its
body."
A number of ancient Greek
philosophers tried to explain the
natural events of earthquakes. Stra-
bo mentioned that "earthquakes
occurred more frequently along
coasts than inland."
The oldest earthquakes on
record, dating back 3000 years,
were in China. Such historical
records are crucial to our under-
standing of the relation of earth.
quakes to the geological features of
our earth.
It has been claimed thai the first
biblical mention of earthquakes is
the experience of Moses on Mount
Sinai. A more definite account of a
biblical earthquake is the collapse
of the wall of Jericho around I100
B.C.. and perhaps the destruction of
Sodom and Gomorrah.
During the crucifixion of Jesus.
an earthquake took place.
"And behold the veil of the tem-
ple was torn in two from the top to
the bottom: and the earth did quake.
and the rocks were split. And the
graves were opened; and many bod-
ies of the saints that slept were
raised," Matthew 27: 51-52.
What causes earthquakes? No so
long ago many people believed that
the earthquakes were related to
man's sin.
Most modern scientists say
earthquakes result from the constant
geological reshaping of our earth.
V See OLASEE, on faclna oaae
Environment
The Daily News, Friday, March 29 1996 19
OLASEE CONTINUED FROM PAGE 18
Deadly quakes struck V.I. in 1867, 1918
Because many earthquakes occur
near plate margins, many scientists
believe duIt global geologic forces
that produce valleys, ocean ridges,
and mountains are the underlying
causes of earthquakes.
These global forces, although
not too well understood by scien-
tists, are consequences of tempera-
ture differences in the earth. These
differences, scientists believe, are
from the loss of heat by radiation
into the atmosphere and again of
heat from decay of radioactive
material in the rocks.
Earthquakes are simply the
shaking of the ground. They also
produce waves.
These waves are called seismic
waves, which radiate from sources
somewhere in the outer par of the
earth.
Earthquakes can be violent and
unpredictable. They can cause mas-
sive destruction by creating land-
slides or causing the sea to rise in
huge waves that sweep inland from
the coast causing destruction to
buildings and properties.
In countries where earthquakes
are more frequent. they pose major
economic and social problems.
The Virgin Islands are in one of
the most earthquake-prone regions
of the world. Strong seismic shocks
were recorded for the Virgin Islands
in 1777, 1843. 1867, and 1918.
The earthquakes that struck the
Virgin Islands in 1867 and 1918
resulted in 116 deaths and econom-
ic losses estimated at $4 million in
1918.
The 1867 tsunami, a tidal wave.
was reported to have a height of 27
feet above sea level.
The potential for human and
economic losses are greater today in
the Virgin Islands. Scientists predict
high seismic potential for a major
earthquake here and in Puerto Rico.
The Virgin Islands are classified as
"Zone 4" for earthquake vulnerabil-
ity. the highest damage zone and
the same classification given to
mnny paris of California.
A 1984 study prepared by Geo-
science Associates said, "All earth-
quukes of MMVITI intensity (Modi-
fied Mercalli Scale) have a recur-
rence period of between 110 and
200 years for St. Thomas/St. John
area."
The study further stated that
such an earthquake could occur in
the next 20 years.
Other scientists predict the Vir-
gin Islands will be struck by an
earthquake at any time now.
St. Croix is on a different shelf
platform from St. Thomas and St.
John. However, the Christiansted
and Charlotte Amalie waterfront
areas are vulnerable to an earth-
quake today if one occurs. because
of the filled-in land from which
they were created.
You see, nature is speaking to us
and nobody is paying attention.
Believe me. the big one can come
like a thief in the night.
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