STRATIGRAPHIC SUMMARY. 615 



Middle Ordovicic (Chazyan). 

 Chambersburg limestone. 

 Lower Stones River limestones. 



Lower Ordovicic (Beekmantownian). 

 Beekmantown limestone. 



SUBFORMATION. 



upper Cambric (Conococheague limestone). 



The beds to the top of the Chambersburg limestone are included 

 with the Upper Cambric in the Shenandoah group. Further south, 

 in eastern Tennessee, the section comprises 



SUPERFORMATION. 



Siluric (basal) (Clinch sandstone). 

 Upper Ordovicic (Trentonian). 



Bays sandstone and shales 300-1,100 ft. 



Sevier shales 2,200-4,100 ft. 



Middle Ordovicic (Chazyan). 



Chickamauga limestone 1,600-2,000 ft. 



Lower Ordovicic (Beekmantownian). 



Knox dolomite (in part Upper 



Cambric) 3^500 ft. 



SUBFORMATION. 



Upper Cambric. 



The Upper Chickamauga limestone is in some localities replaced 

 by the Athens shale succeeded by the Tellico sandstone. 



In the Cincinnati dome region, the Upper Ordovicic beds are 

 typically exposed and are classed together as the Cincinnati group 

 (Cincinnatian). 



The following subdivision has recently been published by 

 Foerste,^ the approximate correlation being added. 

 Cincinnatian. 



Richmond (=Queenston shales, Juniata sandstone). 

 Elkhorn beds. 

 White water beds. 



* Bull. Denison University, Nov., 1909. 



