THE MISSISSIPPI RIVER BLUFFS AT COLUMBUS AND 

 HICKMAN, KENTUCKY, AND THEIR FOSSIL FLORA. 



By Edward W. Berry, 



Of the Johns Hopkins University, Baltimore. 



The so-called bluffs which constitute a sharp boundary between the 

 present alluvial plain or bottom of the Mississippi River and the up- 

 lands of western Kentucky, Tennessee, and Mississippi usually lie 

 somewhat distant from the present river channel. The mighty father 

 of the waters impinges on this escarpment at the present time both 

 toward the mouth of the Ohio and in southwestern Tennessee. The 

 resulting river bluffs are famed in history and tradition; they have 

 been landmarks for the Indians, the raftsmen, and the packet-boat 

 pilots, and they are not without interest for the physiographer and 

 geologist. 



It is the purpose of the present brief contribution to show that the 

 basal beds of the Mississippi Bluffs of western Kentucky at Hickman 

 in Fulton County and in the vicinity of Columbus in Hickman County 

 (the latter known as the Chalk Banks) are of Pleistocene age and not 

 early Eocene as has been supposed by the majority of geologists who 

 have studied the region, and consequently are remnants of a post- 

 Tertiary alluvial plain of the Mississippi River at a considerably 

 higher level than the present Mississippi plain. Also to show that the 

 overlying " bluff gravels' ' commonly referred to the Lafayette forma- 

 tion are consequently Pleistocene and not Pliocene in age and that 

 they are of fluvial origin. 



Without an exhaustive study of the early literature which would be 

 without profit in the present connection it is difficult to say who first 

 studied the Hickman and Columbus Bluffs. Sir Charles Lyell visited 

 the region and makes some interesting suggestions regarding an earlier 

 Mississippi plain about 200 feet above the present one, both in the 

 account of his second visit (vol. 2, chap. 34) and in the fifth edition of 

 his Manual (pp. 121-122). David Dale Owen and Leo Lesquereux 

 visited the Chalk Banks, 2 miles south of Columbus, just after the 

 middle of the nineteenth century and were fortunate in discovering 

 and collecting impressions of leaves in the basal portion of the sandy 



Proceedings U. S. National Museum, Vol. 48— No. 2074. 



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