Munn described the Quaternary of the Foxburg and Clarion quadrangles in
Pennsylvania, where the same Pleistocene problems are involved. They
present an account of the different views regarding the high-level
terraces and the abandoned channels. They concluded, as did Campbell,
that these terraces and channels dated back to the early Pleistocene and
probably to the Kansan stage. Figure 17 is a reproduction of Shaw and
Munn’s figure 10, on their page 12. It represents a section across
Allegheny River at Parker’s Landing, Armstrong County, Pennsylvania. The
uppermost gravels in the figure would be those of supposed Kansan age;
while the lowermost are those laid down during the last glacial stage,
the Wisconsin. In the materials of the high terraces one may expect to
find fossil vertebrates of the early Pleistocene, as in the case of the
mastodon reported from Stewartstown, West Virginia (p. 116). The
conditions of burial should, however, be carefully studied and recorded;
for it would be possible for remains to be left at a later time on such
a terrace and to be covered up by earth washed down from above.
On page 254 an account is given of finding a musk-ox skull near
Steubenville, Ohio, on a terrace about 75 feet above the low-water mark.
The region of the western part of West Virginia, western Pennsylvania,
and northeastern Ohio is interesting because of its history during the
late Pleistocene. The reader is referred to Leverett’s monograph, “The
Glacial Formations and Drainage Features of the Erie and Ohio Basins”
(Monogr. U. S. Geol. Surv., vol. XLI, 1902, pp. 88–158, with figs.).
Leverett essays to show that the upper part of the Ohio River, the
Allegheny, and the Monongahela with its branches at one time emptied
into Lake Erie. The connection was made through Beaver River, which now
flows into the Ohio, and Grand River, in eastern Ohio, now emptying into
Lake Erie. When the Wisconsin ice filled Lake Erie and occupied its
southern shore the mouth of Grand River was dammed and the water could
escape only to the south. The flow was reversed, and after it had
reached the top of the divide it entered the stream that then
represented the head of the Ohio. When at length the mouth of Grand
River was reopened, the new channel had been cut so deep that most of
the streams of western Pennsylvania and West Virginia continued to flow
down the Ohio. Leverett’s figure representing the preglacial drainage of
the upper Ohio region is here reproduced (fig. 10).
NORTH CAROLINA.
(Map 39.)
Our knowledge of the Pleistocene geology of North Carolina is at present
confined almost wholly to the Coastal Plain of the State. The most
recent general discussions of the geology of this region are found in
volume III of the North Carolina Geological and Economic Survey, 1912.
The authors who contributed to this volume are William Bullock Clark,
Benjamin L. Miller, L. W. Stephenson, B. L. Johnson, and Horatio N.
Parker. L. W. Stephenson has furnished an article on the Cretaceous
deposits, and in his numerous geological sections he has referred to the
Pleistocene materials there found. Benjamin L. Miller wrote on the
Tertiary formations and likewise noted the Pleistocene materials found
in his sections. The most important part of the volume for the student
of the Pleistocene is Stephenson’s article on “The Quaternary
Formations,” which occupies pages 266 to 290. Clark, Miller, and
Stephenson united in a chapter on the “Geological History of the Coastal
Plain of North Carolina.” Clark, besides, deals with the “Correlation of
the Coastal Plain Formations.” In addition to numerous plates and
text-figures, a colored map shows the area covered by the surficial
formations of the Coastal Plain and another the distribution of the
formations exclusive of the surficial. Finally, Miller and Stephenson
presented a bibliography which includes 150 titles, occupying pages 44
to 73.
According to Clark and Stephenson, the Pleistocene of North Carolina
comprises five formations; the oldest is the Coharie, farthest removed
from the coast and lying back against the so-called Lafayette, itself
supposed, with some doubt, to belong to the Pliocene. Toward the coast
there come in, in succession of position and time, the Sunderland, the
Wicomico, the Chowan, and the Pamlico. These formations are described as
forming more or less well-defined terraces having higher and higher
elevations as they are followed back from the coast. The Pamlico nowhere
exceeds 25 feet above sea-level. The Chowan varies in elevation from
about 25 feet to about 50 feet. The Wicomico formation slopes from about
50 feet up to about 90 or 100 feet. The Wicomico may attain elevations
of from 140 to 150 feet at the western border. The Coharie varies from
about 160 feet along its eastern border to as much as 235 feet along its
western border. From its western border each formation sends up the
rivers prolongations into or across the next formation toward the west.
Each terrace may present along its coastward border an escarpment of
varying elevation and obviousness. The Coharie and Sunderland formations
are regarded by the authors named as being correlated with the
Sunderland of Virginia and Maryland, although the Coharie may be really
Pliocene. The Wicomico is equivalent to that called by the same name in
the States farther north, while the Chowan and the Pamlico together are
correlated with the Talbot of Virginia and Maryland.
The area occupied by the Pamlico is extremely narrow or absent along the
southernmost third of the coast of the State. At longitude 77° the
boundary between it and the Chowan turns and runs north, very slightly
to the east, striking the northern boundary of the State at about 76°
15′. Just south of Albemarle Sound its width east and west is nearly
equal to that of all the other Pleistocene formations at that latitude,
taken together.
Clark, Miller, and Stephenson (op. cit., p. 300) accept the theory of
McGee that during Lafayette times, probably in the late Pliocene, the
Coastal Plain was depressed some 500 feet below its present level and
covered by the sea. Into this sea were poured, by the rivers coming down
from the higher lands to the west, the clay, sand, and gravel, sometimes
boulders, which make up the so-called Lafayette. Somewhat later the
region was uplifted enough to expose the Lafayette deposits and they
suffered erosion. When the Coharie formation began to be laid down the
sea-level must have been about 160 feet higher than at present; it
continued to rise until it reached an elevation of about 200 feet. A
subsidence and a succeeding elevation occurred, during which the
Sunderland terrace was produced. In like manner the succeeding deposits
and terraces are supposed, by the geologists named, to have been
formed—the Wicomico, the Chowan, and the Pamlico.
One objection already offered (p. 346) to this theory to account for the
deposits belonging to the Lafayette and the formations of the
Pleistocene is that, instead of beds of sea-shells, remains of marine
fishes, porpoises, and whales, there are found scattered here and there
over this region the bones and teeth of elephants, mastodons, horses,
and other land animals. In maintaining this objection it is not
necessary to assume that the lower parts of the Pleistocene area have
never been submerged.
The writer has caused to be prepared a map showing the geographical
distribution of the five formations referred (in the work cited) to the
Pleistocene. It is based on the maps found in that volume. It shows also
the localities where fossil vertebrates have been discovered, and where
marine fossils and land plants have been secured (map 39).
One difficulty met with in our study of the distribution of the finds of
extinct vertebrates in North Carolina, as elsewhere, arises from
carelessness in recording and preserving proper data. In several cases
here to be considered, no more is known than that a fossil has been
found in a certain county. Happily, more is known in many other cases.
Examination shows that no fossil vertebrates are known to have been
found in North Carolina within the area of the Coharie formation, but
that mastodons have been met with in the areas of all four of the other
formations as laid down in Stephenson’s map, plate XIII of the work
cited above. Horse remains, too, seem to have occurred within all the
areas last noted. This does not mean necessarily that these remains were
buried in the corresponding formations. A mastodon may have lived long
after the Sunderland was laid down and his remains have become buried in
some isolated deposit, say of Pamlico times; or, the remains may be
found within the area of Pamlico, but really buried in underlying
Chowan. Each case must be decided on the evidence bearing on it.
Mention is made on page 155 of the finding of a tooth of _Elephas
columbi_ about 9 miles below Wilmington. Whether this was buried in
Pamlico deposits close along Cape Fear River, in Chowan deposits which
prevail there, or beneath these, in Wicomico, it is impossible to say. A
short distance below this place was found a tooth of _Mammut
americanum_.
On page 190 is given an account of the discovery of a tooth of _Equus
leidyi_ in what was supposed to be Miocene marl in the vicinity of
Elizabethtown, on Cape Fear River, in Bladen County. Miller (op. cit.,
p. 248) states that the Pleistocene about Elizabethtown rests usually
directly on the Cretaceous, but that south of the town are found some
patches of Miocene marls. The region about this town is mostly occupied
by the Sunderland formation, but the Wicomico extends up the river far
above the place. It is, however, mapped as lying mostly on the north
side of the river. It seems pretty certain that the horse-tooth occurred
in the Sunderland, probably at its base.
Mastodon remains, as stated on page 115, have been found in Pender
County, but where is not known. Along the coast is a narrow strip of
Pamlico. The southeastern half of the county is occupied by the Chowan,
the northwestern by the Wicomico.
Mastodon teeth have been found in Duplin County, but there is no record
as to exact locality, depth, or matrix. The southeastern two-thirds of
the county is covered by deposits of the Wicomico, the northwestern
third by Sunderland. The mastodon probably belongs to one or the other
of these. The Pleistocene deposits are, however, underlain by Tertiary
rocks, and possibly the mastodon came from these and belongs to a
different genus.
On page 116 will be found an account of remains of a mastodon, probably
_Mammut americanum_, which was found near Jacksonville, in Onslow
County. Three of the supposed Pleistocene formations are found near
Jacksonville. The Pamlico comes up the New River quite to the town.
Immediately at the town is (following Stephenson’s map) the Chowan. The
southeastern border of the Wicomico comes down nearly to the town. In
which of the three areas the teeth were discovered we do not know. A
case is here furnished which illustrates the need of most accurate
observation and record of locality, depth, and character of materials.
As stated on page 116, teeth and tusks of _Mammut americanum_ have been
obtained at Maysville, Jones County. The writer does not know exactly
the place where the remains were discovered. The region about Maysville
is occupied by the Chowan formation, but the Pamlico sends an extension
up White Oak River as far as Maysville.
Remains of both _Mammut_ and _Elephas_ have been reported from Carteret
County. In 1828 (see p. 117) Elisha Mitchell stated that remains of the
elephant and mastodon had been met with in digging the Clubfoot and
Harlow Canal. This canal passed from Neuse River to Newport River. In
1876 (Senate Ex. Doc. No. 35, 44th Congr., p. 17) S. T. Abert
transcribed, from an earlier report made by Professor Olmstead, a
geological section taken in this canal. The excavation went to a depth
of 16 feet. The uppermost of the four layers consisted of the peaty mold
usually found in the swamp. The next layer was made up of a
yellowish-brown potter’s clay. The third layer consisted of sand and was
full of sea-shells and fossil remains of “mammoths” (mastodons) and
elephants. The shells belonged to species now found near Cape Lookout,
principally conch, scallop, and clam. The layer below this was blue
clay. In the case here presented there can hardly be a doubt that the
stratum containing the shells and the bones belonged to a Pleistocene
formation older than that assigned to the Pamlico.
On page 145 is described a tooth of _Elephas primigenius_, dredged up in
Core Creek, forming part of the Inland Waterway in Carteret County. The
conclusion seems unavoidable that this boreal animal had been driven to
this southern latitude during one of the glacial stages, and one
naturally thinks of the latest one, the Wisconsin; but it may have been
at a much earlier time. A mastodon jaw has been secured in the same
canal.
Doubtless the locality in North Carolina, the most important to the
student of Pleistocene vertebrate palæontology, is that reported long
ago on the northern shore of Neuse River, 16 miles below Newbern. As
stated on page 117, in a mention of the mastodon bones discovered, H. B.
Croom seems first to publish a statement concerning the animal remains
found there. Some of his identifications were certainly wrong. According
to Harlan (Amer. Jour. Sci., vol. XLIII, 1842, p. 143), there were
secured remains of elephant, mastodon, hog, elk, deer, horse, seal,
cetaceans, a tortoise, snake, fish, shark, and skate. As in another
case, Harlan may have mistaken worn teeth of _Bison_ for teeth of the
hog (_Sus_). For our purpose the most important animals of the list are
the elephant, the mastodon, and the horse. According to Croom, the
animal remains were found in a marl pit. He was informed by the owner
that in an upper layer there were found teeth of sharks and fragments of
bones of marine fishes, mingled with sea-shells. In a deeper layer, 20
to 25 feet below the surface, there occurred the remains of land
animals, together with sea-shells of great variety. Croom thought that
some teeth belong to the hyena, and Foster reported the hippopotamus;
but in both cases the identifications were wrong.
Conrad (Amer. Jour. Sci., vol. XXVIII, 1835, pp. 107–110; Proc. Nat.
Inst. Prom. Sci., vol I, pp. 191–192) reported that the bones of animals
found here were water-worn, black, and silicified. He concluded that
they had been brought down the Neuse River and mingled with sea-shells.
The fossiliferous stratum did not rise anywhere more than 10 feet above
the river. In the first publication quoted, Conrad published a list of
66 mollusks in this stratum, of which 7 were not yet known as living
species and 2 others are noted as new. According to this list, less than
90 per cent are recent. He referred the deposits to his newer Pliocene.
In the second publication cited he concluded that the stratum belonged
to the post-Pliocene. Stephenson (op. cit., p. 289) refers to the
investigations made at this locality. It is not improbable that the
deposit which furnished these fossils belongs to the earliest
Pleistocene stage, the Nebraskan. The same may be said about the coquina
rock mentioned by Stephenson which occurs at Old Fort Fisher, in New
Hanover County (op. cit., p. 289, plate XXVIII).
On page 115 the writer refers to a lower jaw of a mastodon found by the
geologist W. C. Kerr, near Goldsboro, and described by Joseph Leidy. The
jaw was reported to have been found in gravel overlying Miocene marl.
The writer believes that the mastodon belonged to the species _Mammut
progenium_. Goldsboro, on Neuse River, is near the western border of the
Sunderland formation, but the Wicomico is prolonged up the river far
above Goldsboro. According to Stephenson and Johnson (op. cit., p. 475),
Miocene sands and clays are found over a portion of the northern part of
the county (Wayne). The geological age of this mastodon depends more on
the age of the gravels in which it was found than on the age of the
terrace, although the writer is willing to concede an early Pleistocene
stage for the terrace.
A mastodon tooth has been found (see p. 117) somewhere in Wilson County.
The county is covered mostly by Pleistocene of Sunderland age, but a
small part of the western end is occupied by the Coharie; while,
according to Stephenson’s map, both the Chowan and the Wicomico follow
up Contentnea Creek into Wilson County. The geological age of the
mastodon is doubtful.
At Greenville, Pitt County, have been found remains of _Equus
complicatus_, perhaps also of another species of horse (see p. 191).
While supposed to have been found in Miocene marls, the tooth belonged
without doubt to the Pleistocene. Pitt County is occupied by four
Pleistocene formations, Pamlico, Chowan, Wicomico, and Sunderland. The
probability is that the horse-teeth were found in an early Pleistocene
deposit.
As indicated on page 117, remains of _Mammut americanum_ have been found
in Pitt County, possibly at Greenville.
As noted on page 117, a tooth of _Mammut americanum_ has been found at
or near Tarboro. Nothing more is known about its origin. At this place
are found deposits belonging to the Chowan, Wicomico, and Sunderland
formations; it is impossible to say from which the tooth was derived.
Emmons (Geol. Surv. North Carolina, 1852, p. 56) reported finding
mastodon bones in marl-pits on the farm of Mr. Knight, on the banks of
Tar River, in Nash County, 3 miles west of Rocky Mount. The same
Pleistocene deposits occur here as at Tarboro. The bones were supposed
to have been buried in Miocene marl, and this may have been true. If so,
they belonged to some other species of mastodon than _Mammut
americanum_.
On page 191 is given an account of the discovery of teeth of _Equus
leidyi_ which were washed up on the beach at Plymouth. This town is on
Roanoke River, several miles from Albemarle Sound, and on the border
between the Pamlico and the Chowan formations. Our determination of the
geological age of the teeth must be based on other evidence than that
furnished by the discoverers.
Elsewhere in this work is given an account of finding a part of a skull
of a walrus at Kitty Hawk. It was probably during the Wisconsin glacial
stage that this animal lived along the coast as far south as Charleston.
As to the geological age of the Pamlico formation, the geologists who
have contributed to the report of 1912, the volume cited, hold that it
belongs to late Pleistocene. The writer believes that the formation was
laid down at a much earlier time. The mastodon jaw and the tooth of
_Elephas primigenius_ found in the Inland Waterway Canal may have been
buried there during the prevalence of the Wisconsin ice epoch; but, on
the other hand, this may have happened during an older Pleistocene
stage.
It will be observed that the Pamlico becomes very narrow along the
southern third of the coast of North Carolina. In South Carolina it may
be represented by one of the older Pleistocene deposits recorded by
Sloan; in part possibly by the Wando clays or the Sea island sands. In
the author’s view, it is pretty certain that the Pleistocene molluscan
fauna which had been found in the Clubfoot and Harlow Canal and at the
locality below Newbern corresponds to the Wadmalaw in the vicinity of
Charleston. It seems to appear at the southeastern corner of the State,
at Southport, and again in the northeastern corner in Dismal Swamp.
According to Shaler (10th Ann. Rep. U. S. Geol. Surv., pt. I, 1890, p.
315), a collection of mollusks made near the northern border of the
swamp was submitted to Dr. W. H. Dall. There were 29 forms, of which 24
are yet existing, 5 extinct. There were, therefore, 17 per cent of
extinct forms. Dall regarded the deposits as belonging to the Pliocene;
the writer believes that they may be referred to the Nebraskan stage of
the Pleistocene.
From a study of mollusks collected later in the Dismal Swamp Canal,
Woolman (Proc. Acad. Nat. Sci. Phila., 1898, pp. 414–428) concluded that
they belonged to a time not earlier than late Pliocene and possibly as
late as the Pleistocene. Darton (U. S. Geol. Surv., Folio 80) referred
the deposits to the Pliocene. Stephenson (op. cit., p. 290) states that
recent investigations have led to the conclusion that the beds should be
referred to the Pleistocene. The parties in such a dispute may
compromise by referring the beds to the Nebraskan stage. It seems
probable that the Chowan formation belongs to a stage a little later
than these mollusk-bearing beds and represents a strip of old coast
marsh, inhabited by elephants, mastodons, horses, and various other
animals.
In discussing the causes which led to the production of Cape Hatteras,
Professor Shaler (Proc. Bost. Soc. Nat. Hist., vol XIV, 1872, p. 117)
remarked that the hard shelly limestone which comes to the surface just
above high-tide level along the shore of the mainland from Newbern to
the mouth of the Roanoke River looks much like the shell-bed found near
Charleston, South Carolina.
SOUTH CAROLINA.
To the reader who wishes to know what work has been done on the
Pleistocene geology of South Carolina, two papers may be recommended.
The first of these, historical in nature, was published in 1890 by
Professor Joseph A. Holmes (Jour. Elisha Mitchell Sci. Soc., vol. VII,
pp. 89–117), the second in 1905 by Dr. Griffith T. Pugh (Thesis,
Vanderbilt Univ., pp. 1–74). Those who have contributed most to a
knowledge of the palæontology of this formation are Tuomey, F. S.
Holmes, Leidy, Dall, Dall and Harris, Earle Sloan, and G. T. Pugh. J. A.
Holmes, Tuomey, F. S. Holmes, and Dall have made important contributions
to the knowledge of the invertebrate animals. For our knowledge of the
vertebrates we are indebted principally to F. S. Holmes and Joseph
Leidy. The author who has dealt most recently and in considerable detail
with the stratigraphy of the Pleistocene deposits is Earle Sloan, State
geologist (Bull. No. 2, ser. IV, South Carolina Geol. Surv., 1908, 479
pages). From these authorities we learn that, while the larger part of
the Coastal Plain may be to a greater or less extent overlain by
deposits referable to McGee’s Columbian, the deposits which bear fossils
are confined almost wholly to a narrow strip along the coast. In this
strip have been found the numerous mollusks listed and described by
Tuomey, F. S. Holmes, and W. H. Dall, as well as most of the species of
vertebrate fossils. The fossiliferous deposits do not usually extend
back from the coast more than about 10 miles.