THE CONTINENT 



Ross Ice Shelf on the west, consists of a series of 

 tabular mountains. 



Their horizontal structure is due to the level-bedded 

 character of the main sedimentary formation of sandstone, 

 which has been stififened by massive intrusions of a later 

 dolerite in the form of very extensive sills. Since the base 

 of this formation has been proved to be of Devonian age 

 at least, vve have to regard the whole area as one of great 

 stability and freedom from lateral earth movements. The 

 sandstone formation has an enormous extension, for it is 

 found in Adelie Land in latitude 68° S. and judging 

 from Amundsen's photographs probably also in latitude 

 86° S. — Debenham, 192 1. 



The sandstone is very uniform in composition, 

 though the lower beds in this huge formation are less 

 pure as thin beds of limestone and shale are to be 

 observed. Apparently the sandstone rests on a level 

 surface of granite, but generally the junction is masked 

 by intruding sills of dolerite. However, the latter seem 

 in places to have lifted the level sandstones bodily ofif 

 the granite. In the scarp below Mount Lister (thirteen 

 thousand feet) the sandstone with its included sills of 

 dolerite is at least five thousand feet thick. 



Ripple marks and sun cracks seem to indicate shal- 

 low lakes or pools during sedimentation. The cement 

 is either calcareous or siliceous or even bituminous in 

 places. Charring of included woody stems is to be 

 noticed, but this may be due to the intrusion by the 

 dolerite, perhaps in Cretaceous times. 



Coal has been found in the Beardmore outcrops and 



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