INTRAFORMATIONAL PEBBLES IN THE RICHMOND 

 GROUP, AT WINCHESTER, OHIO 



AUGUST F. FOERSTE 

 Dayton, Ohio 



Ripple-marks, measuring two feet or more from crest to crest, 

 occur at numerous horizons in the Ordovician rocks of Ohio, 

 Indiana, and Kentucky, but are abundant especially in the middle 

 parts of the Richmond group, where they characterize the upper 

 part of the Waynesville formation and the lower part of the imme- 

 diately overlying Liberty formation. Among the occurrences of 

 ripple-marks discussed by Prosser, in his recently published paper 

 on the "Ripple-Marks in Ohio Limestones," 1 the following belong 

 to the lower part of the Liberty formation: Elk Run, a little over 

 a mile east of Winchester, Ohio (Figs, i, 2); Cherry Fork, at 

 Harshaville, 6 miles east-southeast of Winchester; and Treber 

 Run, 5 miles southeast of Harshaville. The ripple-marks described 

 by Joseph Moore and Allen D. Hole from a small western tributary 

 of the Whitewater River, 5 miles southwest of Richmond, in 

 Indiana, and those described by W. P. Shannon from the bed of 

 Salt Creek, 3 miles west of Oldenburg, 38 miles southwest of Rich- 

 mond, also occur in the lower part of the Liberty formation. At 

 the Ridenour Mill, 5^- miles northwest of Oxford, Ohio, the ripple- 

 marks described by Nelson W. Perry 2 occur both in the lower part 

 of the Liberty and in the upper part of the underlying Waynesville 

 formation. In fact, over a large part of Ohio and Indiana, ripple- 

 marks are fully as abundant in the upper part of the Waynesville 

 as in the lower part of the Liberty, and the list of localities might 

 be multiplied almost indefinitely. Ripple-marks occur also near 

 the top of the Brassfield formation at numerous localities in south- 

 ern Ohio (Figs. 3, 4) and northern Kentucky, east of the Cincin- 

 nati axis. 



1 Jour. Geol., XXIV, No. 5 (1916), pp. 456-57. 



2 Am. Geol., IV (1889), 326-36. 



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