204 HOLLAND : CHARNOCKITE SERIES. 



CHAPTER VII. 



Correlation with Foreign Rocks. 



(/) Comparison with the "Pyroxene-granulites!' 



Rocks of this nature have been found to have a wide dis- 

 tribution as members of the Archaean cryst- 

 The Saxon granulite area, allines, and their mode of origin has formed 

 the subject of much discussion. Naumann 1 

 considered the Saxon granulites to be eruptive in origin, and 

 J. Lehmann, in his'great work Untersuchungen uber die Entstehung 

 der altkrystallinischen S chief ergesteine % brought forward an 

 abundance of evidence to show that the granulites and pyroxene 

 granulites had consolidated like granitic rocks at great depths 

 and assumed their present gneissose structure on account of 

 the pressures caused by ancient sediments; and thus in a modified 

 sense, Lehmann confirmed the conclusion of Naumann. But between 

 the date of the publication of Naumann's papers (which only sup- 

 ported with more detailed evidence the conclusions originally stated 

 by Weiss in the commencement of the century) and the appearance 

 of Lehmann's memoir in 1884, various contradictory views were 

 expressed concerning the Saxon granulites and pyroxene-granulites 

 as well as about the similar rocks in Bohemia, Bavaria, Austria and 

 Scandinavia. In all these cases, however, the pyroxene granulites 

 appear to have been regarded as members of the Archaean crystalline 

 series, and none of them has been found to be intrusive into rocks of 

 undoubtedly sedimentary origin. 



Whilst admitting that the evidence is too incomplete to 

 permit a definite conclusion, Adams has de- 

 Canadian pyroxene- scribed some occurrences of pyroxene-granulites 

 g--anuHtes. 



in Canada which suggest their igneous origin. 2 



The pyroxene-granulites of the area described by Adams differ 



» Lehrbuch d. Geognosie, Vol. II, p. 184. 



2 " Report on the Geology of a portion of the Laurentian area lying to the north of the 

 Island of Montreal." Ann. Rept. Geol. Surv. Canada r m (iSg6), Vol, VIII, Part J. 



( 86 ) 



