PART II 



MESOZOIC AND CENOZOIC HISTORY 

 OF THE DRIFTLESS AREA 



In Part I the various principles involved in the erosional 

 histories of regions were outlined and each principle was 

 analyzed, without special reference to any given region. 

 In Part II it seems possible to summarize and emphasize 

 the principles discussed in Part I and at the same time to 

 contribute something to the history of a region in which 

 much work has been done, on which much has been written, 

 but concerning which there has been some difference of 

 opinion. 



All who have worked in the Driftless Area within recent 

 years have noticed that many of the divides within small 

 districts are roughly accordant in level. Most students of 

 the region have concluded that the even-topped divides are 

 remnants of raised peneplains and that more than one cycle 

 was involved in the erosional history of the surfaced There 



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