The Key West citizen. [volume] (Key West, Fla.) 1879-current, 1947-04-24
HURRICANES HERE.

~. II was prepared BY G. Wythe
Cooke and Stuart Mosson in CO
with the United States
Geological survey.
THE FLORIDIAN PLATEAU
The frontispice Of this work
shows . model Of the sOuaheast-
ern part Of North ,America in
Guiding sThe Tloridian Plateau"
Few except interes&ad scientists
ever heard Of this appendage of
the Sunshine State. The clay
model which is teaaatifully re-
produced in halftone. shows the
State Of Florida standing in has
relief on a submerged lower
plane. The edges Of the, lower
plane divide the deep waters Of
the Atlantic Ocean from the deep
waters Of the Gulf of Mexico.
Thus set up in the plaster mod
ell. the entire plat, state and all,
comprises 1.-The Florida Plateau
A study of the photograph of
the plateau shows that more Of
it is below the surface of the
west Of the Florida peninsula
and keys than is west of them.
The axis of the plateau trends
north Is degrees west: and il be-
gins just south of Key West
island. passing up under Braden-
ton, Sarasota, Cedar Keys and
Madison. Nearly all of the Flo
rida peninsula hes east Of this
center axis.
The Floridianl plateau is act
ually a great protection OF the
North American continent, ex-
tending like a narrow shelf most
~ only slightly submerged. along
the ocean and. Cult coasts, broad
est west of the peninsula and un-
DERIVING the entire length Of y.
Scientists have found that the
water in which the submerged
shelf lies IS generally less thsn
so fathoms 600 feet) deep.
The geolosists say this great
rock table has been ia
existence since very ancient time.
The land far beneath the Keys
and the State of Florida at large
is neither coral nor limestone.
although that is what is visible
or becomes exposed on excava-
ton. Rather, the foundations on
which the state is built-the sup
port of the great, submerged
shelf, are made up OF mica,
quartz and other types OF rock
which have folded, crumbled and
faulted in ages past; and
this basement support is nearly
5000 feet below the sea level.
Faultsd Rock at Alee let I
In Florida only one single deep
well has been driven where the
faulted rock was sampled 4,lO0
feet down. This showed a mica
quartz structure. The test bor-
ings were made near York In
Marion county.
Some Key Westers may re-
member that in the search for an
underlying source of fresh water
other than rain-water for the
Island City a 2,Q0O-foot test well
was driven in Jackson Square in
1895. No reef rock was found. The
bare fact of this drilling appears
in Judge jefferson B. Brownies
"Key West, the Old and the
New" 50
Investigating further, the con-
ditions surrounding the driving
of the Jackson Square we'll this
writer secured a copy of the Bull
letin of Agassiz Museum OF Com
parative Zoology, Harvard Uni
versity, written by Edmund Otis
Hovey in Dec. 1896. Rock Samples
were made every Is feet, and six
pages in the form Of a table set
forth the findings. A smaller
table gives the chemical analysis
of the samplings at Is different
depths.
The fact is that in the Jackson
Square effort to find potable wa
Ter, geology and chemistry proved
hat underneath Key West land
probably all of the Keys) is an
almost perfectly pure lime rock
typical at the surface, and for
about Is feet under the surface.
Beneath that, however, almost all
Of the Agassiz samples indicate
4 fine or coarse. more or less
sand rock, va
lied by beds of limestone or por-
nus rock. Small bits Of loose
,vules showed in about half OF
he samples. indicating a shallow
water origin for much of the Is
and of Key West. The most SOL
d rock of all was between SO and
rs feet from the surface. Smap
mounts of quartz interested TIE
chemists at three points. %, u
md 1875 feet.
The Floridian Plateau IS sid
O have remained out of wa1er
Turing the early periods OF pc
.arth's history. but later was COW
red by the sea. Higher up on
he clay model of the Floridian