572 P. E. RAYMOND TRENTON OF TENNESSEE AND KENTUCKY 



the succession may be well obtained from Professor Miller's Eeport on the 

 Georgetown Quadrangle/ with certain nornenclatorial modifications set 

 forth by him in his later report (1919) on the Geology of Kentucky. 



The lower Maysville (Mount Hope) is believed by Foerste to be repre- 

 sented in the upper part of the Garrard sandstone, which is really a 

 siliceous limestone. The Eden, which does not seem to be readily sub- 

 divided, is called the Million shale, and consists of thinly bedded lime- 

 stone and marlite, with a thickness of 120 to 200 feet. At the base, thin 

 layers of limestone contain Cryptolithus tessellatus, Plectambonites 

 rugosus, and an abundance of columnals of crinoids. 



The Cynthiana consists of thinly bedded blue limestone -which weathers 

 to a rubbly mass and contains numerous fossils, Cyclonema varicosum 

 being considered most characteristic. The thickness is about 35 to 60 

 feet in central Kentucky, but increases northward, where the 50 feet of 

 Point Pleasant beds on the Ohio Eiver raise the total thickness to 100 

 feet. The lower and more widespread part is known as the Greendale. 



Beneath the Cynthiana. is the Lexington series, the upper member of 

 which varies from place to place. On the northern and eastern sides of 

 the basin the Cynthiana rests upon the Woodburn, but on the west there 

 intervenes the Perryville, which may have from one to three members. 

 These are, in descending order, the Cornishville, the Salvisa, and the 

 Faulconer. The Cornishville appears to be a very local bed, found only 

 in Mercer County, and contains the same fauna as the Benson. It is only 

 5 feet thick. Beneath is the Salvisa, a "birdseye" limestone, dense, buff, 

 weathering white, and containing Tetradium and ostracods. The thick- 

 ness varies from to 15 feet. At the base is the Faulconer, which is 

 often a single bed 5 to 8 feet in thickness, made up of shells of gastropods. 

 As stated above, these formations occur on the southwestern flank of the 

 arch and drop out in descending order northward, so that the Cynthiana 

 rests in places upon the Salvisa, in others upon the Faulconer, and more 

 generally upon the Woodburn. The interpretation of this condition 

 may be discussed later. 



The Woodburn is a highly phosphatic limestone with rather numerous 

 fossils. It is 50 to 60 feet in thickness and differs faunally from the Ben- 

 son in the presence of Columnaria alveolata. 



The Brannon beneath is merely a useful horizon-marker, its limestone 

 being siliceous and furnishing chert on weathering. It is 7 to 10 feet 

 thick, with few fossils, but often shows a contorted layer which suggests 

 the effect of subaquatic slumping. 



Kentucky Geol. Survey, ser. 4, vol. 1, pt. 1, 1913, p. 317. 



