DEVONIAN FISHES OF IOWA 47 



SYNOPTICAL TABLE OF THE DEVONIAN FORMATIONS OF IOWA* 



SERIES 



STAGE 



SUBSTAGE 



Upper Devonian 





State Quarry limestone and Sweetland Creek 

 beds 





Lime Creek 



Owen beds 

 Hackberry beds 



Middle Devonian 



Cedar Valley 



Not yet subdivided 





Wapsipinicon 



Upper Davenport limestone 



Fayette breccia or Lower Davenport beds 



Independence shale 



Otis limestone 



Lower Devonian 





Not represented 



*"Compiled from earlier Survey Reports (vols. VII-IX). 



REVISED TABULATION OF THE DEVONIAN SEDIMENTS OF IOWA, 

 ACCORDING TO S. CALVIN 



SERIES NAME 



FORMATION NAME 



THICK- 

 NESS 



(Feet) 



CHARACTER OF ROCKS 



Upper Devonian 



State Quarry 



Lime Creek 

 Sweetland Creek 



40 



120 



20 



*Limestone, mostly brachiopod co- 

 quina 



*Mostly shales 



*Shale (*A11 three units locally 

 developed features, each 

 lying unconformably on 

 the Middle Devonian) 



Middle Devonian 



Cedar Valley 

 Wapsipinicon 



100 

 60-75 



Limestones, shaly limestones, some 

 dolomites in the northern counties 



Limestones, shales, shaly lime- 

 stones 



