186 PHYSIOGRAPHY, GEOLOGY AND MINERAL RESOURCES

glomerates are mainly composed of pure quartz grains and pebbles,
which are commonly cemented by means of silicious materials. These
coarse deposits are also frequently cross-bedded and are very irregular
in both their extent and sequence. Important deposits of fire-clays
are found in the Pottsville formation. They occur at two horizons,
one above the middle of the upper half of the formation and the other
in a similar position in the lower portion. Overlying the upper fire-
clay deposit is a thin seam of coal which has been exploited to some
extent at the Mount Savage mines and may prove of value at other
points. The thickness of the formation is between 300 and 350 feet.
THE SAVAGE FORMATION. —The Savage formation, so called from
Savage mountain, Maryland, is the lowest of the coal-bearing forma-
tions in western Allegany and Garrett counties and occupies the basal
portion of the basins within the synclines, which are outlined by the
Pottsville conglomerates. The deposits consist of shales and sand-
stones in which are interbedded several coal seams. The most val-
uable of these coal seams is known as the " Six-foot Vein, " which is
found at the top of the formation. It is the most important coal seam
next to the " Big Vein " of the Elkgarden formation. Another seam
of coal of some importance, which, however, seldom reaches 3 feet in
thickness, is found about 30 feet from the base of the formation.
There are also one or two seams of smaller proportions which have
never been regarded of economic importance. The sandstones and
shales are very variable, the sandstones often becoming shaley. The
thickness of the formation is about 150 feet.

THE BAYARD FORMATION. —The Bayard formation, so called
from Bayard, West Virginia, overlies the Savage formation, above
described, and has in general the same area of distribution. The
deposits consist of sandstones in which are interbedded three workable
seams of coal. The lower portion of the formation consists of rather
thick-bedded sandstones in which are interbedded thinner sandstones
and shales and an unimportant coal seam. The middle of the forma-
tion consists of shales, with thin-bedded sandstone in which are inter-
stratified the three workable seams of coal, viz.: the " Three-foot
Vein, " near the base; the "Two-foot Vein, " which is some 50 feet
higher; and the " Four-foot Vein, " which is at the top of this division.