270 



The middle Huron limestone is usually a cTose-textured. semi-crystal- 

 line, gray fossiliferons limestone wbieli varies in thickness from 5 to 30 

 feet, averaging about 16 feet 



The upper limestone averages about 15 feet in thickness, is more nearly 

 crystalline in structure, varies from dark to light gray in color, and con- 

 tains many crinoid stems and bryozoa. It takes a fine polish and resembles 

 marble when so treated, but does not hold its polish when exposed to the 

 atmosphere. 



The general section in the area under discussion is : 



10 — Shale and sandstone of Pennsylvanian a^c, which is uncon- 

 formable on the beds below. Huron (Chester) Group. 



Ft. 

 Upper — Limostone and shale, calcareous, grading- from 



limestone. br.?cciated limestone at bottom to shale at top : 



limestone composed lai'gely of bryozoa with few 



foraminifera ; locally known as marble 25 



Upper 8 — f^andstone. a lu'avy bed of ferruginous, reddish, brown. 



sandstone. or white, hard or soft, laminated 40 



Middle T — Limestone, crystalline, generally light colored, oc- 



I'rcestone. casionally ooliti;. foraminiferal 6—21 



Middle <> — Shale, argillaceous or arenaceous, weathers red in 



sandstone. places 20-2o 



3 — Sandstone, similar to upper, except much more cross- 

 bedded 25 



4 — Shale, dark. Ijituminous . 0-12 



Lower '■'> — Limestone, thin lii'dded. oi'ilitic or lithographic 2—5 



limestone. 



Lower 2 — Sliale. arenaceous or sandstone i— 12 



sandstone. Mitchell limestone. 



1 — Limestone, white, finely ocHitic. 



SUMMARY OF PUEVIOfS WORK. 



Cox. in a report on the geology of Greene County\ says : 

 "Sub-Carbonferous Limestone. — At the mouth of Fish Creek, in the 

 northern part of the county, limestone belonging to the Chester group of 

 the sub-carboniferous formation, outcrops in the bluff bank of the creek, 

 and is exposed to the depth of l." to 20 feet, and is at this place overlaid by 

 drift, but at a short distance to the southwest it i>s increased by the addi- 



♦ 1st Ann. Kept, Geol, Survey Ind., 1869, p. 87. 



