CHAPTER V. 



CORRELATION AND CRITICISM OF ANALOGOUS AREAS. 



1. GENERAL. 



Crystalline schists have now been reported from widely separated parts of the 

 Antarctic continent. Large areas of metamorphic rocks can, therefore, be assumed 

 to exist under the ice sheet. They have already been regarded as forming the ancient 

 platform on which the central part of South Victoria Land was built.* The present 

 knowledge of the distribution of these rocks indicates that they form the platform of the 

 Great Antarctic Plateau. 



In the Ross Sea region the known extent of the gneisses has been extended by 

 Shackleton's expedition and by Scott's last expedition. They have been proved to exist 

 in King Edward VII. Land on the east. They are now known to range on the west 

 to Adelie Land and to Queen Mary Land. Dredgings from the " Challenger " expedition 

 indicate that they probably extend still further west, and they have been recorded 

 from West Antarctica. 



Streaks of hornblende schist are found associated with the gneisses in the Kukri 

 Hills, in South Victoria Land, by Ferrar. Amphibolites and pyroxene granulites have 

 been recorded from the moraines by the Shackleton expedition.! Amphibolites and 

 hornblende schists have also been mentioned in the description of the rocks obtained 

 by the " Belgica."J 



In Antarctica, as elsewhere, amphibolites are found in manifold forms wherever 

 the crystalline schists appear over a considerable area. Large areas of crystalline 

 schists appear in every continent, and any attempt to correlate occurrences immediately 

 becomes a tabulation of areas of Archaean rocks, and this is unnecessary here. As a 

 consequence of the lithological similarity of most Archaean terraines it follows that any 

 theory correctly deduced from one area should immediately find wide application. The 

 interpretation of one area should materially assist the interpretation in all other areas. 

 That this has not been the case has been in some measure responsible for the more or 

 less disorganised condition of the study of metamorphic areas, and for the complexity 

 that is commonly associated with their study. More particularly, conflicting opinion 

 has been responsible for Cole's description of amphibolites as puzzling rocks. 



* Natural History, voL I., Geology, H. T. Ferrar, Nat. Ant. Ezped., Brit. Miu., p. 25. 



tGeol. vol. II., Brit. Ant. Ezp., Mawmon, Walkom. 



t ' RerolUU da Voyage du S. Y. Belgica.' " Expedition AnUrctique, Beige, Cteologie II., Teil, Dragomir Surtek, 1912. 



f " Rocks and their Origin," Q. A. J. Cole, p. 148. 



