REVIEWS 



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As an appendix the authors present their correlation of the pre- 

 Cambrian rocks of Ontario, western Quebec, and southeastern Ontario. 

 They follow Lawson in calling the older granites Laurentian and the 

 younger ones Algoman. They drop the name Huronian because they 

 think confusion of application has ended its usefulness. They group 

 the sedimentary rocks of the classic Huronian district at Bruce as 

 "Animikean," and correlate with them the Cobalt and Whitewater 

 series and the Ramsey Lake Conglomerate. All post-Algoman, pre- 

 Keweenawan rocks are classed as Animikean. Pre-Algoman, post- 

 Laurentian rocks are "Temiskamian." This name covers the Sudbury, 

 Temiskaming, and Hastings series. For the group including the 

 Keewatin and Grenville they propose the name "Loganian." They 

 think it unnecessary to retain the name Coutchiching, nor do they con- 

 sider that the position of those beds has been proved to be below the 

 Keewatin. 



Their classification is as follows: 



Keweenawan. Upper copper-bearing rocks of Lake Superior. Igneous rocks 

 are both massive and in flows. Sedimentary rocks are little 

 altered in horizontal positions. 

 Unconformity. 

 Animikian. Upper Huronian, Cobalt series, etc. Quartzite, arkose, con- 

 glomerates in usually only gently folded positions. 

 Great unconformity. 

 Algoman. Lorrain, Moira, Killarney, Younger Laurentian granites. 



Generally massive, color pink. 

 Temiskamian. Lower Huronian, Sudbury series. Quartzites, arkose, con- 

 glomerate, Hastings limestone. Usually dips at high angles 

 and is schistose. 

 Unconformity. 

 Laurentian. Granites and gneiss. Color typically gray. 

 Loganian. Grenville and Keewatin. Highly metamorphosed. Lime- 



stones, iron formations, and igneous flows. 



T. T. Q. 



