AN ABANDONED PLEISTOCENE RIVER CHANNEL 

 IN EASTERN INDIANA. 



Rush and Decatur counties in southeastern Indiana are at 

 present drained by Flat Rock creek and Clifty creek. The 

 former has its source in Henry and the latter in Decatur county. 

 Both flow in the same general southwesterly direction, and 

 occupy deep channels which they have eroded in the hard and 

 homogeneous limestone of the Niagara age. They discharge 

 their waters into the east fork of the White river, the Flat Rock 

 above the City of Columbus and the Clifty below. During one 

 of the later stages of the Pleistocene period, and perhaps 

 extending into the recent period, these counties were drained 

 by a stream whose channel had a width of forty rods and a 

 depth of ten or twelve feet, as shown by its well-marked banks 

 composed of coarse river gravel. The elevation of the upper 

 part of this stream was thirty feet above that of the rock bed of 

 the recent streams. It had a more southerly course than these, 

 having its point of departure from the present Flat Rock creek 

 near Rushville, and its point of union with the present Clifty 

 creek near Milford. As indicated by the map, the river may be 

 described in four sections. 



I. From a point about three miles above Moscow P.O., the 

 old channel, called in this region " Hurricane," may be traced in 

 a southerly course midway between the Flat Rock creek and the 

 Little Flat Rock creek until it encounters the latter near the 

 county line where the latter's course is westerly. Through- 

 out this stretch the old channel has an elevation considerably 

 higher than the modern streams. Comparatively little water 

 now runs through this channel except in flood time. 



II. From the point where the old channel encounters the 

 present Little Flat Rock creek to a point about a mile below 



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