ILLINOIS STATE GEOLOGICAL SURVEY CIRCULAR 480 



The emphasis today placed on interdisciplinary approaches to science is by no 

 means new to paleobotanists, who have for some time been aware of the need for 

 a combined geological and biological approach to paleobotany. The story of paleo- 

 botany involves both geologists and botanists and includes their discoveries and 

 interpretations . 



The history of paleobotany in the Illinois Basin is largely centered around 

 plants of Pennsylvanian age, although some studies of Devonian, Mississippian, 

 Cretaceous, and Pleistocene plants have been made. The Pennsylvanian sedi- 

 mentary rocks of the Illinois Basin, or Eastern Interior Basin, include vast coal 

 resources, which make it natural that many important developments in paleobotany 

 should originate there. The basin, a spoon- shaped structural depression, under- 

 lies most of Illinois and extends into adjacent portions of Indiana and Kentucky. 



In about two-thirds of Illinois, Pennsylvanian rocks occur at the surface 

 or immediately beneath Pleistocene glacial deposits. At least 75 coal seams of 

 Pennsylvanian age are present in the Illinois Basin, and most of the fossil plants 

 come from the coals, roof shales, and sideritic nodules in the shales. Many of 

 the coals have been given numbers and/ or names, but many of the designations 

 differ from state to state (fig . 1 ) . 



MIDCONTINENT 



ILLINOIS 



INDIANA 



WESTERN KENTUCKY 



APPALACHIA 



SERIES 



GROUP 



FORMATION 



MEMBER 



GROUP 



FORMATION 



MEMBER 



FORMATION 



MEMBER 





VIRGILIAN 



o 



CC 

 O 

 GO 



en 



Z 

 < 

 UJ 



_) 

 O 

 2 



Mattoon 



Shumway Ls. 

 Calhoun Cool 

 Shelbyville Coal 

 Opdyke Coal 

 |Fnendsville Coal f 



o 

 cc 

 o 



GO 

 </> 



z 

 < 



LU 



_l 



o 



5 



Mattoon 





Henshaw 



"Baker'coal 



.Monongahelo Fm., 



E 



U. 



.c 

 o> 



o 



E 

 a> 

 c 

 o 

 o 



MISSOURIAN 



Lisman 



Bond 



Bond 





Unnamed coal 



Modesto 



Chapel (No.8)Coal 



Potoka 



Parker Coal 



DESMOINESIAN 



Shelburn 





Id 

 111 



Z 

 < 



LxJ 



Carbondale 



Danville (No.7) Cool 

 Herrin (No.6) Coal 

 Springfield- 



Harrisburg (No.5) C 

 Summum (No. 4) Cool 

 Francis Creek Shale 

 Colchester (No.2) C. 



z 



OUJ 

 o 



Dugger 



Danville CML 

 Herrin Coal 



> 



Z 

 UJ 

 X OJ 



o cc 



UJ o 



_l 

 _l 

 < 



Carbon- 

 dale 



Noll Coal 

 No.9Coal 



SchultztownC 



Petersburg 



Springfield C.V 



Linton 



Colchester C.IHo 



Spoon 



DeKoven Coal 



Murphysboro Coal 

 Rock Island (No DC 



UJ 

 Ul 



or 

 o 



z 

 o 

 o 

 o 

 < 

 cc 



Staunton 



Unnamed Coal 



DeKoven Coal 

 BellCoal 



Tradewater 



0_ 



cc 



CD 

 UJ 



_l 

 _l 



> 



1- 

 y- 

 o 

 a. 



Brazil 



Minshall Coal 

 Lower Block Cool 



ATOKAN 



O 



cc 

 o 

 o 

 o 



2 



Abbott 



Willis Coal 



Mansfield 



"Hindostan 

 Whetstone beds" 



Caseyville 





MORROWAN 



Caseyville 





Pig. 1 - Correlation of Pennsylvanian strata in the Illinois Basin and adjacent regions. 

 Names of significant members mentioned in text are shown (after Kosanke et al., 

 I960; Shaver et al., 1970; Smith and Smith, 1967; and Mullins et al., 1965). 



Since the exploration for coal in the Illinois Basin revealed the widespread 

 abundance, diversity, and complexity of fossil plants in the Pennsylvanian strata, 

 much has been learned of the Pennsylvanian flora and its evolution. Most of the 

 paleobotany studies of the Illinois Basin have been made in this century, and 

 some of the pioneer paleobotanists are still active in research, although most of 

 them no longer work in the basin. They have generously shared with us their re- 

 collections of past events and of paleobotanists they knew, some of whom areun- 



