RIPPLE-MARKS IN OHIO LIMESTONES 



469 



were about two inches above their greatest depressions, and the distance 

 from one crest to the next was on the average about 28 inches. They sloped 

 northwards a little more steeply than southwards. This wave-marked layer 

 is only from one to two inches in thickness, and immediately overlies a 

 great mass of pebbles, imbedded in the Clinton just beneath. These pebbles 

 sometimes project strongly into the sandy layer above, which shows the 

 wave-marks. The pebbles are on the average larger than at any place where 

 pebbles have so far been seen in the Clinton. Plenty of them are 12 inches in 





Fig. 4. — View of ripple-marks as formerly shown in the old Schoepfle quarry, 

 Sandusky, looking southeast. Photograph by C. W. Piatt. 



diameter, and many of them range between four and eight inches. As usual, 

 the pebbles are only an inch to an inch and a half in thickness. Lithologically 

 they are similar to the sandy stratified layers of the Clinton limestone, found 

 characteristically in the lower half of the Clinton in this part of the state, and 

 occurring also at higher levels. If there had been any doubt hitherto about 

 the Clinton age of these pebbles, it was dispelled by the fossils found in some 

 of the pebbles at this locality. 1 



Sharpsville. — On Turtle Creek, above Sharpsville, in the western 

 part of Highland County, ripple-marks were noted in the Brass- 

 field limestone; but there was not an opportunity to measure 



1 Jour. Geol. Ill (1895), 184. 



