TEAYS RIVER, HUNTINGTON, WEST VIRGINIA
 |
 |
| Plate F-26 |
Map |
This enhanced Landsat mosaic shows the region where the
states of Ohio, Kentucky, and West Virginia join near Huntington,
West Virginia. The distinctive high-density dissection of the
uplands results from intricate dendritic drainage on the generally
flat-lying sediments of the western Appalachian Plateau.
Almost all the rocks are Paleozoic sandstones, siltstones, and shales,
which are easily eroded in the humid-temperate climate.
Figure F-26.1 is an
aerial photograph showing such topography in great detail, and
Figure F-26.2 is an
oblique low-altitude photograph.
The Appalachian Plateau dissection noted above can be
considered to display a mature phase of erosion. In the
idealized concept of fluvial dissection of a landscape, proposed
by W. M. Davis (1899), youthful topography is characterized
by broad undissected interstream tracts and divides. Steep gullies
may be actively eroding as in the Loess Plateau of China. In
mature dissection (Figures F-26.1 and F-26.2), the drainage
divides are reduced to sharp ridges, resulting in a minimum of
interstream uplands. This produces the maximum possible relief.
In old age, the divides are reduced, although some high-relief
areas may be left as erosional residuals. Removed of its genetic
implications, the scheme can provide a useful description of drainage
evolution.
The Ohio River is the major drainage element in this
study area, but it has only occupied its present position
since the Late Pleistocene. A prominent paleovalley
(stippled pattern on the location map and "bands"
without ribbon of river in photo) represents the ancestral
trunk river in this region. This paleovalley is part of the
Teays River system, the preglacial drainage from which the
present Ohio River evolved. The preglacial Teays drained
northwestward from the Blue Ridge of Virginia across West
Virginia and Ohio. Its course can be traced by numerous wells
in Ohio, Indiana, and Illinois, where its westward-trending
valley is buried by glacial drift (Thornbury, 1969).
The advance of Pleistocene ice over the Teays River
course caused the drainage to shift from the Teays route
to a route roughly paralleling the glacial boundary. The
modern Ohio River does the latter. However, the timing
of the shift is uncertain because of difficulties in dating the
complex sequence of drift in the region. Paleomagnetic
studies of fills in the Ohio portion of the Teays Valley
indicate an age greater than 0.7 million years.
The portion of the Teays Valley extending east-west
from Huntington is filled with Late Tertiary alluvium and Early
Pleistocene lacustrine clay. The data indicate that the Teays was
an active system until Early Pleistocene glacial ice dammed its
upper course. Then, either the divide near Portsmouth was
overtopped by the lake or piracy from the evolving Ohio system
captured the Teays headwaters. Paleomagnetic data indicate that
the lake existed from approximately 1.7 to 1.0 million years ago.
The final result was the shift of Appalachian Plateau drainage
to the Ohio River course. The modern Ohio River Valley carries
the later Pleistocene fluvial record of this region. The uppermost
sediments of the Teays paleovalley consist of loess, emplaced by
eolian activity during the cold/dry phases of the Pleistocene.
Landsat 2386-15280 and-15282, February 12, 1976.
Continue to Plate F-27 |
Chapter 4 Table of Contents |
Complete Table of Contents |
Geomorphology Home
|
 |