If these caves, we see in the Florida Caverns Park area, were formed
under water, how is it possible to walk through them today? This is an
obvious question which requires an answer. If rocks formed under marine
waters are exposed on the land surface today it is obvious that the land
has been raised out of the sea, or the sea has lowered. From geologic
evidence it is known that Florida has been rising since late geologic
time. This elevation is believed to be caused by downwarping at the mouth
of the Mississippi River, where many thousands of box car loads of
sediment are dumped each day, accompanied by adjustments in the earth’s
crust and the elevation of land areas surrounding the delta of the
Mississippi River.
Then there is a second cause by which these caves are made dry. Everyone
has heard that ice caps the North and South poles of the earth, but few
people realize that, if all this ice melted, the level of the sea as it
is known today would be higher by about 110 feet. If all polar ice
melted, the Chipola River at Florida Caverns, would become a salt bay,
Marianna a seaport town, and a bay beach would be located near the park
area. However, do not sell your present beach property too quickly since
this polar ice is known to be melting only a few inches a century.
[Illustration: Well-lighted, underground trails make accessible Florida’s
amazing network of underground passageways. The temperature remains at
about 63 degrees, F. throughout the year. In addition, natural rock
gardens, wildlife, historical values and recreational facilities make
Florida Caverns one of the South’s outstanding State Parks.]
Considering the sub-tropical climate of Florida, isn’t it peculiar that
ice had so much to do in shaping our land surface? As a matter of record
all of the surficial deposits making up the large part of the land
surface of Florida were created and shaped during the geologic past (one
to ten million years ago) when ice piled up on the poles and moved down
over lower latitudes or when this ice was being melted. In the United
States as this ice piled up on the North Pole and moved down over most of
the middle western states, the water forming this ice came from ocean
basins and the water in them was lowered as much as three to four hundred
feet. At this time much of the Gulf and Atlantic bottoms was uncovered,
land streams cut their valleys much deeper, ground water circulated much
more vigorously and rocks through which it passed were dissolved faster.
Later as this ice was melted the lower parts of stream valleys were
filled with salt water and the streams became sluggish and deposited
sediment in their valleys to make their flood-plains. Ground-water
circulation was retarded and the bottoms of the Gulf and Atlantic were
again covered. This uncovering of the bottoms of the Gulf and Atlantic
followed by covering constitutes a cycle. Five of these cycles have been
recognized in Florida, and the red sands, clay and gravel that make up
the surface of most of Florida represent former bottoms of the Gulf and
Atlantic, now raised out of these seas by land movements.
Today we are living in a period following a time the northern and
southern extremes of the earth were covered by ice, and this ice is still
melting off of these areas.
_In 71,000 acres of parks, valued at approximately $50,000,000, Florida
offers the vacationer a natural wonderland he can explore. Within these
park areas the visitor can discover for himself the “true” Florida by
car, along foot trails, navigating tropical rivers and streams—or by
following elevated boardwalks through hauntingly beautiful swamps._
[Illustration: Stalagmites resulting from varied origins. The center one
was formed from the intergrowth of several stalagmites. The deposit on
the left was developed as a series of flat basin-like parts, over which
water splashed and cascaded to the floor, the basins being inclined in
various directions. The right stalagmite began as did the left one but
the basins were soon eliminated and the growth was made more regularly.]