BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Vol. 12, pp. 395-444, PLS 35-41 OCTOBER 31, 1901 



SILURIAN AND DEVONIAN LIMESTONES OF TENNESSEE 



AND KENTUCKY 



BY AUGUST F. FOERSTE 



(Read before the Society December 28, 1900) 

 CONTENTS 



Page 



Silurian formations * 396 



The Cincinnati anticline 396 



Relationships and characteristics of Silurian outcrops in Kentucky and 



Tennessee. 396 



Subdivisions of the Silurian 397 



Silurian sections at South Tunnel and Bledsoe 397 



Lithological character and thickness of Tennessee Silurian formations. . . . 491 



Explanation of the section ^01 



Variations in Clinton limestone 403 



Variations in Osgood bed ... 405 



Constancy of Laurel limestone 407 



Constancy of Waldron shale 407 



Constancy of Louisville limestone 407 



The Silurian-Devonian unconformity 408 



Contrast of variations in thickness of Silurian subdivisions 414 



Evidence by Silurian formations as to age of Cincinnati anticline 416 



Silurian overlaid by Devonian beds 416 



Silurian overlaid by other Silurian beds 418 



Professor Safford's observations 420 



Silurian exposures on the upper Cumberland, southern Kentucky 421 



Devonian formations 424 



Devonian limestone absent along Cumberland river, Kentucky. 424 



The Pegram limestone 425 



The Chattanooga Black shale 426 



Variations in thickness 426 



Sandy and earthy layers at base of Black shale 427 



Phosphatic character of base of Black shale. 427 



Erosion of Black shale during early deposition of the Waverly 428 



Cause of thinness of Black shale in southern Tennessee 429 



Source of the detrital material at base of Black shale 429 



Cause of erosion shown at the Silurian-Devonian contact 430 



Ordovician — Richmond group 431 



General relationships 431 



The Leipers Creek bed, Tennessee 432 



LVII— Bull. Geol. Soc. Am., Vol. 12, 1900 (395) 



