STRATIGRAPHY OF OHIO WAVERLY FORMATIONS 765 



the lower 100 feet at least of these sandstones in northern Kentucky, 

 within 45 miles of Portsmouth, are the approximate equivalent 

 of the Byer member in southern Ohio, which there overlies the 

 Cuyahoga or in part passes into the topmost beds of the Cuyahoga. 



PALEOGEOGRAPHY OF THE CUYAHOGA 



The Tohoso and Hocking Valley conglomerate areas. — Herrick 

 thought that the material composing the Black Hand conglomerate 

 came from the northeast/ Stevenson writes of the pebble material 

 of the "Logan" (Orton's usage, Black Hand and Logan of this 

 paper) as follows: ''They can hardly have come from the north, 

 for there the upper Logan, Reid's Olive Shales, is very fine in grain, 

 while farther south it becomes coarse, as it is in northwest Pennsyl- 

 vania, east from Reid's localities. It is equally improbable that 

 the pebbles come from the east, for the deposits become finer east- 

 ward toward the central line of the basin, beyond which they become 

 coarser. The sands must have come from the western side."^ 



The immediate source of the conglomeratic material in the Cuya- 

 hoga of central Ohio undoubtedly was to the south-southeastward. 

 Lamb's observations in northern Ohio on conglomerates of unde- 

 termined horizon indicate the same direction as the source of the 

 material.^ It is not possible at present to state under precisely 

 what conditions the conglomerate sandstones of the Toboso and 

 Hocking Valley facies were deposited, but it is the writer's opinion 

 that they are the result of deltal action under marine conditions. 

 The structures observed, however, do not in any way correspond 

 to the structures suggested by Barrell as criteria of such an origin ."^ 



These sandstones were deposited under conditions of strong 

 current-action which swept pebbles up to an inch in diameter to 

 their present position; which laid down thick beds over wide 

 areas at an inclination of 5° to 10° (much steeper than the foreset 

 beds of the large deltas of the present, according to Barrell) ; which 

 generated in these beds cross-bedding of the most pronounced kind, 



' C. L. Herrick, Bull. Sci. Lab. Dennison Univ., II, Part I (1887), 9, 10. 

 ^ J. J. Stevenson, Bull. Geol. Soc. Am., XIV (1903), 91. 

 3 G. F. Lamb, Ohio Naturalist, XIV (1914), 344-46. 



1 Joseph Barrell, "Criteria for the Recognition of Ancient Deltal Deposits," 

 Bull. Geol. Soc. Am., XXIII (1912), 377-446. 



