KENTUCKY GEOLOGICAL SURVEY. 



Cincinnatian Series. 



Winchester Group. 



As already indicated, the lower part of Campbell's Winches- 

 ter, as shown at Winchester, the county seat of Clark county, 

 has been traced northward to Point Pleasant and its identity 

 with the Point Pleasant beds established. Lithologically there 

 is not a great deal of change in this distance. The formation 

 contains much more clay than the underlying Lexington and 

 the limestones are not so massive. Under cover, as shown by 

 deep railroad cuts, the limestones and especially the shales are 

 bluish, but towards the surface through oxidation they become 

 yellowish or brownish. 



In the Winchester there first becomes noticeable the regular 

 alternations of limestone and shale which are so characteristic 

 of the Cincirnatian series. No satisfactory explanation has 

 yet been offered why there are these rapid alternations of lime- 

 stone and shale. It may have been that in deposition the argil- 

 laceous and calcareousi matter were indiscriminately commingled, 

 but subsequently through some segregating process the fine 

 calcareous particles were separated from the clay and concen- 

 trated into the limestone layers. The fossils remained where 

 they happened to be, and so are found in either the limestone or 

 in the clay. Some modification of the process due to special 

 conditions may explain the "waved limestones ; r - the explanation 

 that is usually given for these waved layers that they are ripple 

 marks seems to the writer an almost impossible one. 



At several points along the Ohio river between Foster, Ky., 

 and New Kichmond, Ohio, notably opposite Moscow, Ohio, and 

 in the vicinity of Point Pleasant, Ohio, these beds have been 

 extensively quarried and the rock shipped by river to Cincin- 

 nati and other points. The rock makes a much better building 

 stone than the limestone obtained from the hill quarries at, Cin- 



