FLORIDA STATE HORTICULTURAL SOCIETY. 
Il8 
la river. The Tampa Silex beds and 
Tampa Limestone are seen at Ballast 
Point, Tampa. Another thin formation, 
the White Beach is exposed along little 
Sarasota Bay. These several local for¬ 
mations are included along with the pen¬ 
insular limestone to make up what is 
known in the more recent classification as 
the Oligocene of Florida. The rocks of 
these several local formations taken to¬ 
gether make up the surface rocks, except 
for the mantle of sand over a very consid¬ 
erable area of the central and western 
part of the state. 
The Micoene next above has an increas¬ 
ed proportion of clay and shales along with 
some limestone and sandstone. The prin¬ 
cipal area of Micoene extends along the 
East Coast from Jacksonville to Lake 
Worth or l^elow, and reaches in some lo- 
calaties a thickness of five hunderd feet. 
The same time interval is represented 
by a thinner deposit along the Appalacha- 
cola river and west of the river towards 
Pensacola. 
Formations of still later date cover the 
extreme south of the state and local areas 
throughout the istate in general. 
The Florida deposits are all among the 
more recent of the geology time divisions, 
all falling within the Cenozoic or last of 
the large time divisions. The state as a 
whole lies entirely within and is a part 
of the general coastal plains deposits 
reaching from New Jersey on the north 
along the Atlantic coast to the Gulf, and 
west to Texas, embracing as a whole a 
strip varying in width, but averaging 
about loo miles along the coast covering 
the eastern part of New Jersey, Delaware, 
Maryland, Virginia, North and South 
Carolina, Georgia, all of Florida, much of 
the southern part of Alabama, Mississippi, 
Louisiana and Texas. The formations of 
the coastal plains area as a whole are se¬ 
dimentary containing much clay and 
shales and sandstones, lying nearly hori¬ 
zontal or with but slig^^t dip. The sedi¬ 
ment forming these deposits came evi¬ 
dently from higher lands to the north 
and west. 
Owing to the fact that Florida, especial¬ 
ly peninsula Florida, was farther remov¬ 
ed from the source of sediment the pro¬ 
portion of wash from the land was very 
much less, and in the resulting seas an 
abundant shell life was able to develope. 
It thus happens that Florida is exception¬ 
al among the other gulf states in the large 
proportion of limestone it contains. 
As will be gathered from this brief re¬ 
view the Florida peninsula has been ele¬ 
vated above water slowly. That the up¬ 
lifting began at the close of the formation 
of the peninsular limestone is evidenced 
by the appearance of the island areas at 
that time. That the further elevation was 
also gradual and slow is indicated by the 
successive deposits of later formations 
around the island areas. It is assumed 
that the slow upward pushing has brought 
the peninusla up as a large anticlinal fold 
with the highest part of the fold forming' 
the central area of the peninsula. Actual 
observation of anticlinal structure from 
the rocks themselves is difficult owing to 
the mantle of sand covering, and the lim¬ 
ited exposures of rock. That there is a 
dip, however, is indicated by the depth at 
which any recognizable formation is en¬ 
countered in borings. Thus the peninsu¬ 
lar limestone which is found at the sur¬ 
face in Alachua or southern Columbia 
county is encountered in wells at St. Au¬ 
gustine at a depth of 224 feet. Farther 
to the south along the coast an even greaL 
