KENTUCKY GEOLOGICAL SURVEY. 13 



the Winchester shows besides its limestones a consid- 

 erable proportion of clay layers. The next succeeding 

 formation, the Eden, shows a prevalence of shaley and clayey 

 layers. Whether there is an unconformity between the Eden 

 and the underlying Winchester has not been certainly deter- 

 mined. It is probable that slight unconformities, due to some 

 oscillation of the sea bottom, exist between all the groups of 

 formations, Lexington, Winchester, Eden, Maysville and Rich- 

 mond, but that the decided differences lithologically the 

 changes are not sudden, yet on the w T hole pronounced are due 

 to important changes taking place in the geography elsewhere. 

 Where the land was located from which this muddy sediment 

 was derived, whether to the north or south, or both, is not known, 

 but from the fact thtat the Cincinnatian faunas are more lux- 

 uriant in the Cincinnati region than fartheV south, and that on 

 the whole there are more limestones in all the Oincinnatian for- 

 mations there than farther south, it seems a fair inference that 

 the mud was brought by currents from the south or southeast. 

 The Cumberland sandstone and Garrard sandstone, the latter 

 gradual!} 7 replaced by limestone and shale toward the north, also 

 point to a southern origin for the sediment. That the north 

 also contributed material for the growth of the, as yet sub- 

 merged, island, is indicated by the great thickness of Eden or 

 Utica shales shown by the drill in northern Ohio. 



With the close of the Eden there was again a return to condi- 

 tions which permitted considerable limestone accumulations. 

 The Maysville group has a considerable amount of limestone and 

 a large fauna. Occasionally in some of the Maysville formations 

 there are successions of strata with few or no fossils in Ken- 

 tucky, while corresponding equivalent strata in Ohio at Cin- 

 cinnati show abundant fossils. This may be taken as evidence 

 that the movement of muddy sediment from the south contin- 

 ued. This condition of things which began at the close of Lex- 

 ington, or earlier, and continued through Eden and Maysville, 



