396 A. F. FOERSTE — LIMESTONES OF TENNESSEE AND KENTtCKY 



Page 



The Cumberland sandstone of southern Kentucky 434 



Origin of the name 434 



The Fowler limestone 434 



Beds above the Fowler limestone 435 



Beds below the Fowler limestone 435 



Equivalency of Cumberland sandstone and Madison bed 436 



Evidence of Richmond group on age of Cincinnati anticline 436 



Lists of fossils 437 



Clinton fossils west of the Cincinnati anticline in Indiana, Kentucky, and 



Tennessee 437 



Waldron fossils west of the Cincinnati anticline in Tennessee 442 



Louisville limestone fossils at Pegrani and Bledsoe, Tennessee 443 



Devonian fossils found in the Pegram limestone in Tennessee 444 



Silurian Formations 

 the cincinnati anticline 



A low anticlinal fold extends from north of the Ohio river, in a direc- 

 tion about south 25 degrees west, through the central parts of Kentucky 

 and Tennessee. Its crest passes about 15 miles east of Cincinnati and 

 40 miles east of Nashville. It is known usually as " the Cincinnati anti- 

 cline," although the name " Nashville dome " has been used at times 

 for its southern half. 



This fold was in existence in early Devonian, if not in Silurian, times. 

 No Silurian formations occur along the crest of the fold in central and 

 southern Kentucky, or in northern and central Tennessee. The width 

 of the area within which Silurian strata are absent is 40 miles in cen- 

 tral Kentucky ; it is calculated to be about 55 miles in the region of the 

 Cumberland river; and in central Tennessee, according to the observa- 

 tions of Professor Safford, it must be still greater — possibly 80 miles. 



Surrounding this area, and overlapping the Ordovician on the flanks 

 and ends of the anticline, are Silurian strata, the total thickness of which 

 diminishes on a})j)roaching the crest of the fold. 



The result is that Devonian strata rest on Silurian formations along 

 the flanks and ends of the anticline, but along the crest, from north 

 of central Kentucky to southern Tennessee, they rest directly on the 

 Ordovician. 



RELATIONSHIPS AND CHARACTERISTICS OF SILURIAN OUTCROPS IN KENTUCKY 



AND TENNESSEE 



In Kentucky, the most southern exposures of Silurian strata on the 

 western flank of the anticline occur at the extreme southern end of 



