176 J. J. STEVENSOK CARBONIFEROUS OF APPALACHIAN BASIN 



Feet 



1. Ames limestone 3 



2. Red shale 30 



3. Gray shale 100 



4. Coal bed [Anderson] 1 



5. Limestone [Cambridge] 1 



6. Concealed 10 



7. Buffalo sandstone 50 



8. Sandy shale 35 



9. Gallitzin coal bed [Upper] Trace 



10. Sandy shale 35 



11. Lower Mahoning sandstone 55 



giving 317 feet from the Ames limestone to the Upper Freeport coal bed. 

 The Buffalo sandstone is easily followed in all but the western townships 

 of southern Butler; in those it evidently loses its conglomerate character 

 and becomes less important. The Lower Mahoning, very coarse at the 

 east and southeast, becomes shaly westward, while decreasing somewhat 

 in thickness. The Gallitzin horizon is represented by thin coals at 

 numerous localities, there being at least one bed wherever the interval is 

 exposed. The highest is that in the Freeport section; elsewhere the 

 highest is at 70 feet. In Forward township three beds are present at 

 20, 25,. and 63 feet above the Upper Freeport, and two are shown at 

 35 and 60 in Jackson. The Mahoning limestone appears to be wanting 

 throughout. 



The Brush Creek coal and limestone seem to be almost wholly un- 

 represented in the eastern townships. The horizon is recognizable at 

 many places as black, sometimes coaly, shale underlying the Buffalo 

 sandstone, but the coal as such is distinct first in the western third. A 

 Forward Township section shows 6 inches of coal separated by 10 feet 

 of black shale from the overlying Buffalo; it is 115 feet above the Upper 

 Freeport and 52 feet above the Upper Gallitzin. In Connoquenessing 

 it is scattered through the black shale at 119 feet above the Upper Free- 

 port and is 72 feet above a Gallitzin coal. In the southwest corner of 

 the corner both coal and limestone are well shown, the type locality being 

 on Brush creek, in Cranberry township. 



The Cambridge (Pine Creek) limestone, shown in the Freeport sec- 

 tion, is absent at all other localities where its horizon is reached. It is 

 not noted in any of Doctor White's numerous sections, but the Anderson 

 coal bed belonging above it is persistent at 5 to 20 feet above the Buffalo 

 sandstone. The Barton (Bakerstown) coal bed is present in some of the 

 townships along the Allegheny County border at 80 to 85 feet below the 

 Ames limestone, but it is no longer an important member of the forma- 



