56 G 5 . REPORT OF PROGRESS. I. C. WHITE. 



erate layers, although the soft and red shaly constitution 

 'has nearly disappeared. 



The sandstones of the section, however, if they belong to 

 the Mauch Chunk formation No. XI, wear a remarkable 

 lithographical resemblance to the typical rocks of the Pocono 

 formation No. X ; and the cutting off of the section at the 

 dividing plane between the bottom of the 5' dark shale (7) 

 and the top of the 40' pebbly sandstone (8) is arbitrary and 

 hypothetical.* 



There seems to be more shaly layers and fewer sandy lay- 

 ers in the formation outcropping on the northwestern side 

 of the basin ; but the whole thickness remains about the 

 same. 



B. Tlie Pocono Sandstone formation continues the sec- 

 tion downwards thus : — Fig. 7, b : 



8. Sandstone, huffish-white, pebbly, 40' 



9. Shales, buffi sandy, and concealed rocks, f . 200' 



10. Sandstone, buffish-white, massive, 125' 



11. Shales, with sandstone, gray, current-bedded, 265' 



12. Griswold's Gap Conglomerate, white, very pebbly, . . 35' 



The 40' rock (8) is very massive and contains very many 

 white quartz pebbles, and would certainly be identified with 

 the Sub-Olean Conglomerate were our section made in the 

 northwestern counties of the State. 



The 200' buff shales (9) could not be exactly measured, 

 and the thickness may range between 175' and 225'. 



The 125' sandstone (10) has all the Pocono characteristics. 

 Along Roaring branch it is an uninterrupted pile of layers, 

 varying from Y to 4' in thickness, of moderately fine-grained, 

 very hard, somewhat current- bedded, buff colored sand- 

 stone. — Just below Greenville it dips N. W. into the water 

 at an angle of 10° to 12°. — In a notch of the Lackawanna 

 mountain, northwest of Oliphant, it is seen, 100' thick, dip- 



* Others may prefer to include in No. XI, the 40' pel>ble rock (8) and the 

 200' of shales (9,) and draw the line of the top of No. X at the top of the 125' 

 sandstone (10 of Fig. 7, b.) This would increase Formation XI to 410'. 



f Estimated thickness. 



