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and sedimentary rocks together as a structural unit under one 

 term, the same geologists suggest that some local term might 

 have been applied to the basal complex in the Lake Superior 

 country instead of the general term "Archean." 



The correlation of the upper series of the Mesabi and Penokee- 

 Gogebic districts (which are agreed by all to be equivalent to 

 the Animikie series) with the Upper Huronian of the original 

 Huronian area of the north shore of Lake Huron, first worked 

 out by Logan and Murray, is also questioned by certain Cana- 

 dian and Minnesota geologists, who believe that these series are 

 younger than the true Huronian of the original Huronian area. 

 They would correlate Van Hise's Lower Huronian with the Upper 

 Huronian of the original Huronian area, and thus Van Hise's 

 Archean would in large part fall into their Lower Huronian. 



Finally, it is maintained by Canadian geologists and others 

 that the granites classed by Van Hise as Archean are intrusive 

 into the Huronian rocks. Van Hise's position is that the 

 granitic complex contains rocks both older and younger than 

 the Huronian sedimentary rocks ; that the fact that certain 

 granites are clearly intrusive into the sediments does not militate 

 against the evidence offered by basal conglomerates that another, 

 and perhaps larger portion, is really unconformably below the 

 Huronian rocks. 



It would not be possible in a summary of this nature fully 

 to summarize the arguments and reasons which have led Van 

 Hise to the conclusions outlined in the above paper. He has in 

 preparation a final monograph on Lake Superior geology in 

 which these and allied questions are fully discussed in the light 

 of recent developments. In view of Van Hise's close and 

 exhaustive work in the Lake Superior region, which is in many 

 respects a type pre-Cambrian region, and the long period of 

 time during which this work has been carried on, his final state- 

 ment of his position with reference to the geology of the area 

 will be awaited with interest. 



Coleman 1 reports on an examination of the " Lower Huronian" 



'"Iron Ranges of the Lower Huronian," by A. P. Coleman, Tenth Report 

 of the Bureau of Mines, Ontario, IQOI, pp. 181-212. 



