1882.] 48d [White. 



XII being replaced by a green sandy shale which the geologist instantly 

 recognizes as belonging in the subcarboniferous beds. The junction of XII 

 and XI is finely exposed for several rods at this locality, and the former 

 seems to rest with a slight unconformity on No. XI. In the top of No. XI, 

 at the horizon of No. 9, occur valuable deposits of iron ore all along the 

 Cheat river mountains on each side of Chestnut Ridge, and they were 

 formerly extensively mined and used at the Henry Clay, Laurel, Green 

 Spring and other furnaces. It is known as the "Sicisher,"' and "Moun- 

 tain" ore, and was mined by both drifting and stripping, the bed some- 

 times attaining a thickness of 2 feet. 



Were there any doubt about No. 9's being the top of XI, No. 10 would 

 resolve it, for red shale is a factor unknown in No. XII. This red bed seems 

 to hold a constant place in the Mauch Chunk series along Cheat river, 

 having been seen at this same horizon in many localities. The section 

 from No. 13 down, was given me by Mr. Ley, who assisted in drilling a 

 well for oil near the mouth of Quarry run. As will be seen from the sec- 

 tion, it makes the Mauch Chunk shale 300' thick, and the Mountain Lime- 

 stone 85'. 



No. 15, is very probably not all No. X, but the lower portion doubtless 

 penetrates the Catskill, or Chemung, if the former be absent as Prof. 

 Stevenson claims. 



In passing up Cheat river from the mouth of Qviarry run, the rocks rise 

 quite rapidly, and at one-half mile south-east from the localitj^ of the last 

 section, all of the Mauch Chunk shale, and nearly half of the Mountain 

 Limestone have appeared above water-level, where oh the left bank of 

 Cheat, they reveal this succession (Sec. 8) : 



1. Sandstone, current-bedded 10' ■) ^ 



2. Concealed 15' 



3. Red shale 10' 



4. Limestone, fossiliferous, impure 8' 



5. Shales, red and green 15' 



6. Shales, marly 5' , 



7. Limestone, grayish-white, massive 25' "1 tl ^ 



8. Shale, calcareous, very fossiliferous 1' I 3 g 



9. Limestone, massive, gray, to level of Cheat | § ^ 



river (850' A. T. by Bar) 15' J g | 



This little section is interesting from the fact that it exhibits a structure 

 in the basal portion of the Mauch Chunk shale, which is quite common in 

 Fayette and Westmoreland counties. In those counties Prof Stevenson 

 (see Repts. KK, and KKK SdGeol. Survey of Pa.), finds o/ie and sometimes 

 two thin limestones several feet above the base of the Mauch Chunk shale, and 

 the same feature is present all along the Cheat river Canon, as far up as 

 Rowlesburg at least, where I find three thin limestones within an interval 

 of 70' above the Mountain Limestone. (See The "Virginias for July, 1882.) 



FROC. AMER. PHILOS. SOC. XX. 113. 3l. PRINTED NOVEMBER 20, 1882. 



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