OUTLIERS OF THE MAXVILLE LIMESTONE IN OHIO 

 NORTH OF THE LICKING RIVER.* 



By G. F. Lamb. 



(Published by permission of the Ohio Geological vSurvey.) 



It is well known to those familiar with Ohio geology that 

 the Maxville limestone is the uppermost formation of the 

 Mississippian system found in the Ohio scale, that its outcrop 

 is limited in extent, patchy in character, and that the over- 

 lying Pennsylvanian beds rest upon it unconformably. 



William C. Morse, in Bulletin 13 of the Ohio Geological 

 Survey, published in 1910, presents the most complete account 

 of this formation published. It is shown in this bulletin that 

 up to 1910 all the known outcrops of this formation occur 

 south of the Licking River, extending from a point a little 

 southwest of Zanesville, on the north, to the vicinity of Ports- 

 mouth on the Ohio River. It is further shown that the most 

 important area of outcrop lies at the north and extends from 

 near Zanesville southward to the vicinity of Logan — an area 

 about 25 miles long and 10 or 12 miles wide. 



It has long been supposed that this formation once extended 

 to the northern part of the state and was removed by post- 

 Maxville pre-Pennsylvanian erosion. The supposition was 

 based upon the presence of lime cobblestones more or less 

 silicified found at the bottom of the Coal Measure basal con- 

 glomerate, and which were said to carry Mississippian fossils. 

 Since no other Mississippian limestone was known to occur 

 in the state, it was concluded the cobbles must have been 

 derived from the Maxville. 



It is the purpose of this paper, (1) to point out the north- 

 ward extension of this limestone, (2) to throw further light on 

 the origin of the cobble stones, and (3) to emphasize a reason 

 for its absence in the northern part of the state. 



The writer has found various outcrops of this limestone as 

 far as 40 miles north of Zanesville in a belt 10 to 12 miles wide 

 extending northward across Muskingum, Coshocton and into 

 southern Holmes County. They invariably occur in isolated 



*Read before Section E of the American Association for the Advancement of 

 Science, Columbus meeting, 1915. 



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