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NEW YORK STATE MUSEUM 



Summary of classification of the New York Devonic according to John M. Clarke 



DESCENDING ORDER 



System 



Group 



Stage 



Carbonic 



Devonic 



'Pennsylvanian 

 Mississippian 



d 

 o 

 > 

 a; 



o 

 2 



tj 



S 

 o 

 > 



o > 

 Ifl 



c 

 o 



l\ 



-d 

 o 

 a; 



Olean conglomerate 

 Knapp beds 

 Oswayo beds 



(Panama conglomerate) 

 Cattaraugus beds 



incl. Wolf Creek con- 

 glomerate 



Chautauquan 



Senecan 



Chemung beds 

 A (Catskill sandstone, local 

 ( facies) 



' Portage beds 



(Naples, Ithaca, Oneonta, 

 Sherburne beds, local 

 facies) 

 Genesee shale 

 Tully limestone 



Erian 



Ulsterian 



Oriskanian 



' Moscow shale 

 Ludlowville shale 



\ Skaneateles shale 

 Cardiff shale 

 Marcellus shale 



Hamil- 

 ton 



Onondaga limestone 

 Schoharie grit 



I Esopus grit 

 I Oriskany beds 



Helderbergian -{ 



' Port Ewen limestone 



Becraft limestone 

 I New Scotland beds 

 (^ Coeymans limestone 



