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CHAPTER IV. 
GENERAL GEOEOGY OF THE BURGETT8TOWN QUAD¬ 
RANGLE. 
DESCRIPTION OF SURFACE. • 
LOCATION. 
The Burgettstown quadrangle joins the Steubenville on the east, 
lying between 80° 15' and 80° 30' west longitude and 40° 15' and 4(P 
30 north latitude. Most of the area covered by the quadrangle is in 
V ashington County, Pa. A small part of Beaver County is included 
along the north edge and a portion of Allegheny County in the 
northeast corner. Burgettstown, from which the quadrangle receives 
its name, is situated on the Pittsburg, Cincinnati, Chicago and St. 
Louis Railway, near the center of the quadrangle. 
TOPOGRAPHIC FEATURES. 
The streams of the quadrangle are all tributaries of Ohio River, 
but they flow in various directions to reach this stream. Raccoon 
Creek, whose two main branches rise in the southern half of the quad¬ 
rangle, flows directly north through the middle of the northern half. 
On both sides of this stream are main dividing ridges, from which 
the waters flow in both directions—on the east to Chartiers Creek, 
and on the west direct to Ohio River. 
All the streams have cut deep valleys, between which are rounded 
hills whose summits reach from 200 to 300 feet above the main vallev 
levels. The complete dissection of the surface by the smaller streams 
presents favorable conditions for geologic work. 
GEOLOGIC FEATURES SHOWING AT THE SURFACE. 
SECTION OF ROCKS EXPOSED. 
The surface of the quadrangle is composed of the Conemaugh, 
Monongahela, and Washington formations. The total section ex¬ 
posed is about 750 feet. In the northern half the surface outcrop is 
about equally divided between the Conemaugh and the Monongahela 
formations. In the southern half little of the Conemaugh formation 
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