GEOLOGY OF GILES COUNTY, VIRGINIA 
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cian formationA^ Certainly, there is no appreciable gradation in 
Giles County. 
Fossils are rare, but specimens of Dalmanella testuclinaria and 
Plectambonites sericeus were found as well as fragments of 
Triarthrus becki. What faunal evidence there is, as well as the 
stratigraphic position of this formation, indicates a Mid-Ordovi- 
cian age. equivalent in part, at least, to the lower Utica division 
of the New York classification. 
The Moccasin Limestone Subdivided 
Section taken at the Narrows of the New River, Giles County, 
Virginia. First two members are on Virginian Railroad. 
1. Bluish limestone, thin bedded and not obliquely jointed as 
in the rest of the formation. The last two feet of this division 
are separated from the rest by three or four layers which re- 
semble the Chickamauga. Even bedded and calcite veined. Mud 
breccia in this member. 10 feet. 
2. Red to light brown, fine grained, even bedded limestone. 
Jointing is oblique with splintery fragments which are empha- 
sized by weathering. A few layers are bluish gray instead of 
reddish. Beds are from one to fifteen inches in thickness. One 
layer of hard, drab to grey lithographic limestone four inches 
thick about twelve feet from the bottom. Mud cracks are un- 
usually prominent. 90 feet. 
3. Lithographic horizon. Starts up the ravine leading from 
railroad to wagon road. 
a. Hard, dense, blue, limestone layer with small calcite veins. 
6 inches. 
b. Continuation of normal Moccasin. 10 feet. 
c. Second fine grained, hard, lithographic layer, cherty ap- 
pearance. 1 inch. 
d. Continuation of normal Moccasin. 1 ft. 8 inches. 
e. Third lithographic layer. 2 inches. 
The non-lithographic layers seem to be partly lithographic, but 
of an inferior quality. Total, 12 feet, 5 inches. 
4. Gray, greenish to drab, hard limestone in beds three to 
twelve inches in thickness, weathering lighter and having the 
same oblique jointing and splintery fragments as noted else- 
where. 16 feet. 
” Bassler, R. S., ‘Cement Resources of Virginia.” pp. 167. 
