GEOLOGY OF GILES COUNTY, VIRGINIA 
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1. Dark blue to black, heavily bedded limestone with many 
small chert nodules. Productm, Zuphrentis, and Fenestella 
observed. 175 feet. 
The Biuefield Shale 
This shale, which directly overlies the Greenbrier, varies from 
calcareous at the base to sandy at the top, where it is capped by a 
heavy bed of quartzite. It marks the transition period between 
the deposition of limestone below and sandstone above. 
The formation takes its name from the town of Biuefield, West 
Virginia, where it is typically developed, and attains a thickness 
of 1250 feet. The section at the Narrows is also a little over 
1000 feet in thickness. Some horizons are quite fossiliferous in 
the vicinity of Rich Creek, 
The Hinton Formation 
This formation is composed of impure limestones, argillaceous 
shales, sandy shales and sandstones, but it is so heterogeneous 
that no bed may be mapped separately. It is especially well de- 
veloped along the New River in the vicinity of Hinton, West 
Virginia, from which place it takes its name. In Giles County 
there are 1000 feet exposed, but the section is not complete. 
There are several fossiliferous zones in this formation. The 
calcareous beds are rich in flat coiled gastropods. Stigmaria and 
Catamites are rather common in some of the divisions. 
Tertiary Gravels 
Mention must here be made of the Tertiary gravels which are 
found even at considerable altitudes in the open valley between 
Butt and Angels Rest mountains. Some of these deposits occur 
at elevations as much as 350 feet above the present river bed. 
The exact status of these deposits is in doubt, but they may in 
part correspond to the Lafayette or Orange Sand formation of 
Oligocene time, which is found in many of the states just to 
the west of the Appalachians. This formation often has a 
thickness of twenty to thirty feet and is composed of sands, 
gravels, and even rounded boulders. It was derived from the in- 
soluble residue of older formations such as chert and quartzite 
pebbles, together with limestone fragments side tracked by the 
streams before wholly ground up. The color is often yellow or 
orange, and the deposits are quite conspicuous occasionally for 
long distances. This deposit was formed by peneplanation and 
