The Punta Gorda herald. [volume] (Punta Gorda, Fla.) 1893-1958, 1914-03-26
ANCIENT HISTORY OF THE GULF or
MEXICO
Waters Of the Early World Once Covered
Large Portions of the South

Most people know in general way that
large portions of the United States have
in the past been covered by the ocean,
but 1t is perhaps not so generally known
that the continent is now rising In some
places and sinking in others. There Is
every reason to believe that minor move
ments of the land are constantly taking
place. Not so very long ago. in geo.
logic sense, the Hudson river flowed thro-
ugh deep canyon or gorge at New York
city. Soundings show that this gorge
extends through the harbor and far out to
sea- 1t is evident that the land surface
has been lowered in this region, allowing
the ocean to creep in on the land. fill
the old river channel. and in places
wholly submerge it. The submergence
of the land was greater at one time than
1t is now. In excavations for some of
the New York skyscrapers remains of
oysters and other salt water animals
have been found. AS rule the only av-
ailable knowledge in regard to the former
submergence of an area is derived from
the marine shells and other animals
found in deposits laid down by the sea-
BY the nature Of the fossils biologists
are able to tell approximately when the
ocean invaded the land. They have found
evidence of a submergence Of much
greater magnitude and much older than
that which now floods the Hudson Valley.
Gothamites and others need not, how
ever, feel alarmed at this statement of
the ups and downs of the continent, for
while geologically this saomergence is
not so very old. the geologist thinks and
speaks In terms of thousands If not mill
lions Of years.
Along the Atlantic coast, from New
Jersey southwark, 1t Is not unusual to
find quantities of sharks teeth and other
marine fossils in the greensands that
are now located far inland and are used
for fertilizers. In certain sections of the
Mississippi Valley where limestone is
not readily accessible farmer will go
out and gather a wagon load of fossil
oyster shells to burn for lime. The
shark bearing rocks Of New JERSEY ond
the oyster beds of Tennessee are of the
same general age and represent of the Ia
ter of the great invasions of the ocean
on the north American Continent In
geologic parlance these rocks are said to
be of Cretaceous age.
In the course of its Investigations of
the geology Of the country, the United
States Geological Survey has been maxi
ing study of the Cretaceous deposits of
the Eastern States and has found that
the ocean Of that time covered much of
what Is now the Atlantic Coastal Plain.
while the Gulf OF Mexico spread widely
over the central Southern States, prob
ably reaching as far north as Carlo, Ill.
The Ohio was then larger and older
river than the Mississippi. Some Of the
sediments Of this age, now hardened into
rocks, were deposited in shallow sea,
some about the mouths of rivers, and
some prehaps in the flood plains of the
rivers themselves. All these different
types Of sediments, as found In the east
ern Gulf region, are described in the u
nited States Geological Surveys Profess
sional Paper 81, by L. w. Stephenson. In
another portion of the paper Is discus
sion of certain oysterlike shells found in
these Cretaceous rocks, all the known
species being described and figured.
The paper Is of interest to those living
in the eastern Gulf region not only as
illustrating the geology Of the area but
as indicating the distribution of certain
TYPES of rocks. AS the soil is made in
large part by the slow decay of the
underlying rock, it naturally follows that
certain sorts of rock furnish better soil
and subsoil than Others BY means of
the map included in the report the extent
of different geologic formations can be
traced
Professional Paper 81 may be obtained
without cost by applying to the Director
of the United States Geological Survey,
Washington, d. C.