T. E. Savage — Stratigraphy of Southvjestern Illinois. 44^ 



Sys- 

 tem 





Correla- 

 tions 



Location 



of 

 sections 



Descriptions of horizons 











A short break in deposition. 



a 



o3 



a 



CD 



3 



o 



02 

 CD 



.s * 



1—3 «H 



CD +3 



? Pi 



CD 

 o3 



o 



Along the river 1 1/2 miles 



north of Thebes, and also 1 



mile south of Thebes, in 



Alexander county 



3c. Coarse-grained, somewhat oolitic limestone, in 

 layers 12-18 inches thick. Atrypa rugosa, 

 Rhynchotreta sp., Schuchertella subplanus, 

 Whitfieldella billingsana and Lichas breviceps 

 clintonensis are common 3 1/2 ft. 



3&. Fine-grained, dark colored shaly limestone, in 

 layers 4-10 inches thick, characterized by 

 Rafinesquina mesacosta, Schuchertella sub- 

 planus and Dalmanites dance 2 1/2 ft. 



3a. Cape Girardeau limestone : Fine-grained, black, 

 brittle limestone, layers 1-4 inches thick, 

 separated from each other by thin lenses or 

 partings of calcareous shale on the surface of 

 which are exposed Crinoids, Rafinesquina 

 mesacosta, Rhynchotrema sp., Schuchertella 

 missouriensis and Cornulites tenuistriata, etc. 33-38 ft. 











A probable short break in sedimentation. 



a 



03 



V 



O 



7-1 



o 



03 

 ^) 

 03 



S 



.5 

 '3 



o 



=4-1 



if 



CD 



O 



£ 



c3 



•xi 



o 

 | 



o 



East bank of Mississippi river 

 1/2 mile south of Gale, Alex- 

 ander county. 2a in the 

 south part of Thebes 



2b. Bed of grayish-blue shale in which 1-inch bands 

 of more resistant calcareous shale occur 4-6 

 inches apart, bearing Rhynchotrema inozqui- 

 valve ?, Strophomena sulcata, Zygospira recur- 

 virostra,Conradellasi>., and Isotelussj). 18 ft. 



2a. Thebes sandstone and shale : Bluish to brown, 

 shaly sandstone. In the lower part a sand- 

 stone in layers 1/2-2 1/2 feet thick ; the 

 upper portion thinner bedded with a larger 

 admixture of shale. Lingula cf. covingto- 

 nensis the only fossil found 73 ft. 



s 



03 



2 









A long break in deposition. 



33 

 CD 



o 



03 



03 

 O 



«4H 



o 



CO 



CO 



CD 



pf 



o 

 ■+= 



JH 



CD 



H 



cb 

 CD 

 "o3 

 O 



East bank of Mississippi 



river, 3/8 mile south of 



Thebes; S. E. 1/4 sec. 



17, T. 15S.,R. 2W. 



la. Light gray, coarsely crystalline limestone, in reg- 

 ular layers 3-48 inches thick, the upper part 

 characterized by the fossils Receptaculites 

 oweni, Herbertella near occidentals, Platys- 

 trophia biforata, Plectorthis plicatella, Cyrto- 

 lites ornatus and Platymetopus cucullus, while 

 the lower is marked by Receptaculites oiveni, 

 Rhynchotrema incequivalve, Parastrophia hem- 

 iplicata and Triplecia n. sp 68-80 ft. 



