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Terraces op the Whitewater River Near Richmond, Indiana. 



By Allen David Hole. 



INTRODUCTION. 



The terraces referred to in this paper constitute a small part of the 

 complex series of terraces which characterize practically all the larger 

 \alleys in a considerable portion of the glaciated area of the United States. 

 The terraces along the Whitewater Iliver near Richmond have been recog- 

 nized and referred to by a number of ohservers, but so far as the writer 

 Icnows, there is no record of any systematic, detailed study of them prior 

 to 1J)09. n that year Harold Chapman, then a student at Earlham Col- 

 lege, studied carefully under the direction of the writer the terraces within 

 the gorge from Richmond to a point about one and one-half miles south of 

 the city. A continuation of this work for the three forlis of the White- 

 water above the city, extending four or five miles along each fork, was 

 tindertaken by W^endell H. Pitts, another student, and completed by him 

 in 1911. The author has, by permission, used freely the data gathered in 

 these two studies, which covered the areas Indicated on the accompanying 

 outline map. Fig. 1. 



GEOLOGY. 



The geologic formations involved include (1) thin-bedded limestone 

 and intercalated shale of Upper Ordovician age, exposed in the gorge-like 

 valley near the city of Richmond and for some distance above and below: 

 (2) Middle Silurian limestone exjwsed scarcely at all within the limits 

 here referred to, but forming the underlying bed rock in the northern 

 (upper) parts of the area studied; (3) glacial drift of Pleistocene age, 

 both unassorted (moraines), and assorted (valley trains, outwash plains, 

 etc.) ; and (4) deposits of Recent age, mainly alluvial (flood-plains), but 

 including also fans, material shifted by sheet wash, accumulations of 

 talus, etc. 



Sti-ucturally, the bed rock forms a part of the northernmost end of 

 the Cincinnati anticline ; the strata exposed are, however, practically hori- 



