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blown, the materials, including the shells being collected from the terrace 

 surface from the sills deposited by the valley-wide stream. This deposition 

 probably occurred soon after the stream abandoned the terrace level and 

 withdrew to the present deeper third of the valley width. The work was 

 done mainly before the invasion by vegetation of (he terrace, bluff front and 

 upland border, after the retreat of the ice sheet from the region. The loess 

 may be a wind deposit from the bare valley at the close of the Illinoisan 

 ice invasion. This dust may have weathered through a long interglaeial 

 period of time to be covered with later deposits of dust and fine sand swept 

 over the valley from the border of the Late Wisconsin ice which did not 

 reach the present site of Terre Haute, but whose strong moraine lies fifteen 

 or twenty miles upstream near Clinton and Rockville. 



