SOME PRE-CAMBRIAN LITERATURE OF NORTH AMERICA 83 



metamorphism of rocks, since more and more cases of intimate 

 relationship between the occurrence of schists and bathoHthic 

 intrusions, principally granite, have been found as geologic study 

 proceeds. 



Coleman^ presents a summary of the stratigraphy and corre- 

 lation of the pre-Cambrian as adopted by the international com- 

 mittees on correlation, before the British Association at Winnipeg. 



Coleman^ argues that the abundance of carbonaceous shales, 

 limestones, and other ordinary sediments in the Keewatin of 

 Ontario implies the existence of life and climatic conditions not 

 unlike the present. 



Coleman^ infers that uniformitarian conditions prevailed in the 

 pre-Cambrian from the similarity of pre-Cambrian sediments to 

 those of later periods. 



Coleman"* presents a summary on the degree and kind of meta- 

 morphism of the various pre-Cainbrian formations of northern 

 Ontario. The agents of metamorphism as outlined by Coleman are 

 heat, pressure, and solutions. 



Coleman^ presents a historic summary of the methods which 

 have been employed in classifying the Archaean of Ontario. The 

 principal methods, according to Coleman, in the order of their 

 historic development are relative stratigraphic position of forma- 

 tions, lithologic similarity, unconformity, eruptive contact, and 

 basal conglomerates. 



Coleman^ summarizes the principal known events in the history 

 of the Canadian shield. 



'A. P. Coleman, "The pre-Cambrian Rocks of Canada," British Assoc. Adv. 

 Sci. Rept. 79th Meeting, 1910, pp. 474-75. 



' A. P. Coleman, "Climate and Physical Conditions of the Keewatin," Geol. Soc. 

 Am. Bull., XXI, No. 4 (1910), 778-79. 



3 A. P. Coleman, "The Bearing of pre-Cambrian Geology on Uniformitarianism," 

 British Assoc. Adv. Sci. Rept., 79th Meeting, 1910, pp. 473-74. 



4 A. P. Coleman, "Metamorphism in the pre-Cambrian of Northern Ontario," 

 Compte Rendu, Congres Geologique International, 1910, pp. 607-16. 



5 A. P. Coleman, "Methods of Classification of the Archaean of Ontario." Compte 

 Rendu, Congres Geologique International, 1910, Vol. I, pp. 721-33. 



6 A. P. Coleman, "The History of the Canadian Shield," Nature, LXXXIV 

 (September 15, 1910), 333-39- 



