COAL FIELDS OF KENTUCKY AND TENNESSEE
Reprinted with Permission from Dallas Bogan.
The following article is taken from The Cumberland Gap Coal Field
of Kentucky and Tennessee as distributed by the United States Geology
Survey of 1904
The Cumberland Gap coalfield
forms a part of the eastern edge of the Appalachian coalfield in southwestern
Kentucky and northern Tennessee. It lies between Pine and Cumberland
mountains, and extends from Fork Mountain to the heads of Poor and Clover
forks of Cumberland River, having a length of 90 miles and a width of
from 15 to 20 miles. Associated with Pine and Fork mountains are important
faults (breaks in the Earth) making distinct breaks between this field
and the coalfields to the west and north. While this field was originally
part of the same general coalfield, as are the coals areas to the west
and north, more detailed work than has yet been done will be required
to connect the geography of this basin with that of the outside fields,
or to associate the coals across the breaks made by the faults mentioned.
Cumberland Mountain forms the eastern
section of the Appalachian coalfield. All that part of the "coal
measures" that may formerly have existed to the south having been
removed by erosion.
Work was done on these measures in the
seasons of 1902 and 1903 over the central part of the basin, or the
area lying between Log Mountains at the head of Yellow Creek to a north-south
line about 10 miles east of Harlan.
Pine and Cumberland mountains are formed
by the edges of resistant sandstones upturned at angles from 20 degrees
to 90 degrees from the horizontal, and, following the structure, run
nearly straight on northeast/southwest lines. Between these two ranges
lies a mass of mountains of irregular shapes, with irregular and usually
The drainage of the area studied is empties
entirely into the Cumberland River, which if formed by the union of
there forks--Poor, Clover and Martins at Harlan, and which escapes from
the basin by the gap at Pineville. Wallin, Puckett, Yellow, and Clear
creeks are its principal tributaries below the forks. At the Pineville
Gap Cumberland River has an elevation of about 980 feet above high tide,
while the highest points in the area reach an elevation of 3,400 feet.
The mountains rise 1,000 to 2,000 feet above adjacent drainages. The
lower valleys have commonly broad bottoms with abruptly rising side
slopes; the higher valleys are V-shaped.
This basin is structurally a flat-bottomed
trough with sharply bent slopes. The center of the trough lies near
but a little southeast of the Cumberland River, running between Clover
forks on the east and between Stony Fork of Yellow Creek and Clear Creek
west of Middlesboro, Kentucky. In this belt were noted several minor
faults in the gap at Pineville and the territory adjacent on the east.
A fault with a down-throw to the west of over 1,200 feet along the west
face of Rocky Face Mountain; a fault with apparently considerable horizontal
movement. All the small hills in or immediately around the plain at
Middlesboro give evidence of highly confused structure, as though the
shales, which make up a large part of the exposed strata at that point,
had given away with folding and probably faulting under the stresses
which produced the faults just mentioned. The upturning of the rocks
in Pine Mountain is in connection with the great Pine Mountain fault.
The structure in Cumberland Mountain is
part of the western limb of the Powell River valley.
The projection of rocks of this basin
consist of sandstones and shales with coal beds. So far as found, the
fossils show that all of the coal-bearing rocks belong to the Pottsville
group of the Pennsylvanian series. The lower part of the section is
predominately sandy and often of a conglomerate nature.
The upper part of the series of rocks
shows an irregular succession of shales, sandstones, and coals, the
shales and sandstones being in about equal proportions and showing little
tendency toward segregation in particular parts of the section. In studying
the coal content of the upper part of this series of rocks it will be
convenient here to consider separately the Log Mountain area west of
the fault belt from Cumberland Gap to Pineville, and the Harlan region
east of that belt.