30 
ECONOMIC GEOLOGY OF AMITY QUADRANGLE, PA. 
vania it amounts to as much as 80 to 120 feet. In places, but not 
everywhere, it occurs directly below the Thirty-foot sand. 
DEVONIAN SYSTEM. 
ROCKS BELOW THE TOP OF THE CATSKILL RED BEDS (CHEMUNG FORMATION). 
General character. — Throughout the Amity quadrangle the Devonian 
rocks lie far below the surface. As has been said, the top of the sys- 
tem is very indefinite, but it has been provisionally placed at about 
the top of the first red shale below the Fifty-foot sand. 
The Devonian rocks have been penetrated by wells to a depth of 
over 1,000 feet. All these rocks are believed to belong to the Che- 
mung formation. The greatest thickness is recorded in the Mrs. A. L. 
Hawkins No. 1 well (31), near Beallsville. The record of this well is 
very meager, but a number of shallower wells furnish good sections as 
deep as the Elizabeth sand. The deepest complete section is on the 
A. C. Mitchell farm, in West Pike Run Township. The top of the 
formation here is in considerable doubt, as the red beds are less con- 
spicuous than in some of the neighboring wells, and the section is 
therefore made to include all beds up to the Fifty-foot sand. To be in 
harmony with other wells, the top of the Devonian system should here 
be placed approximately •'>() to 50 feet below the bottom of this sand. 
Partial section of rocks penetrated by the A. C. Mitchell well, West Pike Run Township. 
Sand, Fifty-fool 
Sh.fr 
Sand 
Slate 
Sand 
S!at«> 
Sand 
Shells... 
Red rock 
Shells 
Sand, Si ray. . 
Red rock 
Sand. Gordon 
Red rock 
Shells.. 
Slate 
Sand 
Slate 
Sand, Bayard. . 
Slate 
Shells and slate 
Sand, Elizabeth 
Slate 
Shells 
probably Carboniferous 
Catskill beds < 
Feet. 
85 
5 
10 
14 
4 
14 
13 
10 
5 
20 
24 
21 
60 
55 
30 
10 
15 
5 
65 
27 
38 
6 
169 
167 
872 
