SHELBY COUNTY. 167 



Below the last, and included in Nos. 6, 7 and 8 of my section, there is 

 about 96 feet of sandy and argillaceous shale, sandstone and argillaceous 

 limestone, with calcareous and bituminous shale. The upper part con- 

 sists principally of argillaceous shale ; below, the beds are not all 

 persistent, and are interchangeable. The argillaceous shale sometimes 

 assumes the form of a deep blue argillaceous limestone. It crops out 

 near Kaskaskia river, one mile above the mouth of Long branch, 25 feet 

 in thickness, with 15 feet of thin-bedded sandstone separating it from 

 coal No. 15. Near the railroad one mile west of Bobinson's creek it is 

 30 feet in thickness. Its beds are very irregular, with buff shaly part- 

 ings. Its fracture is smooth, conchoidal, the thinner beds shaly, and 

 the only fossils found were two specimens of Chonetes variolata t 



The sandstone (No. 6) is also changeable, both gradually and abruptly. 

 Sometimes it is entirely absent, its place being occupied by sandy shales, 

 as on Little Wabash river; at other places it is a thin-bedded sandstone. 

 Two miles south-east of Shelbyville it changes rapidly to a shale, again 

 to a sandstone, and again to a shale. Sometimes it rests on the coal as 

 at Smith's, then it is separated from the coal by bituminous shales, which 

 1 have seen beginning at 0, and in a short distance increasing to l.J feet 

 in thickness. 



At Lilly's mill a calcareous shale overlays the coal, which, in 200 feet 

 distance, thickens from to 3 feet ; it is divided, after a short distance, 

 by 2 feet of clay shales, and the upper part becomes a tirm bed of lime- 

 stone. 



There are but few fossils in these several beds; in the sandstone, 

 Sigillarioe and Calamites, and probably Cordaites in the shales. In the 

 calcareous shales the fossils are very much crushed, but I could distin- 

 guish Athyris subtilita, Sj>. Kentuckensis, Prod. Prattenianus and Bryozoa. 



The following sections were obtained at the various outcrops of coal, 

 from which the changeable character of the adjacent rocks will be seen. 

 On Copperas creek, west of Nioga, at J. Young's coal bank — 



Ft. In. 



1. Drab and bine shale - 3 



2. Bituminous coaL to 20 



3. Fire-clay 3 



4. Slope 10 to 15 



5. Chocolate and drab colored arenaceous limestone '. 2 6 



6. Slope 5 



7. Sandstone, hard and rough 5 



On Little Wabash, one mile above the mouth of Copperas creek — 



Ft. In. 



1. Clay and drift 25 



2. Clay sha'e 14 



3. A little black slate 



4. Bituminous coal to 22 



5. Fire-clay at top for a few feet, then clay shales, with nodules of ironstone, one nodule with 



zinc-blende, etc 18 



