14 ECONOMIC GEOLOGY OF AMITY QUADRANGLE, PA. 
thickness of 100 to 150 feet. Patches of it occur as far north as 
Odell and nearly to Ellsworth. Several knobs in the vicinity of 
Denningsville are also capped by it. 
ROCKS BETWEEN THE TOP OF THE UPPER WASHINGTON LIMESTONE AND THE TOP OF THE 
WAYNESBURG COAL (WASHINGTON FORMATION). 
Character. — The thickness of the Washington formation varies, but 
in this quadrangle is generally from 300 to 400 feet. The formation 
contains several easily traceable members, which have been desig- 
nated by special names. The following generalized section is given 
by Stevenson" and is believed to be a fair average of the extreme 
development of the formation in this area: 
Generalizt d s< < -'ion of tin Wash ington formation in Washington County. 
Feet. 
Limestone, Upper Washington . 30 
Sandstone 40 
Coal 1 
Sandstone 40 
Limestone, Middle Washington 15 
Sandstones and shales . 60 
Limestone 8 
Sandstone and shale 20 
Shale, hit uminous or coal 1 
Limestone. Lower Washington 20 
Coal, Wash ington 10 
Sandstone, laminated 12 
Coal, Little Washington 1 
Shale 
Limestone 20 
Coal, Waynesburg ''B" 1 
Sandstone 30 
Limestone 8 
Coal, Waynesburg (, A" 2 
Sandstone, Waynesburg 60 
Stevenson 6 also gives a partial section of the Washington forma- 
tion on Cemetery Hill, in the southern part of Washington, as follows: 
Section on Cemeten/ Hill , Washington. 
Feet. 
Limestone, Upper Washington 30 
Concealed . 50 
Coal . .Blossom. 
Imperfectly exposed 80 
Limestone, Lower Washington 12 
Coal, Washinaton 7 
Clay 4 
Sandstone 9 
Concealed - 10 
Limestone 2 
a Second Geol. Survey Pennsylvania, Rept. K, 1876, p. 4*. b Op. cit., p. 248. 
