THE CONTINENT 



twelve thousand square miles of available territory, but 

 it is unlikely that coal measures are developed through- 

 out. Our parties found no coal in the Ferrar-Taylor 

 valleys. Possibly a great deal of coal exists under the 

 Polar Ice Cap at a lower level than in the South Vic- 

 toria Horst, where alone it has been observed so far. 

 Probably it lies two or three thousand feet below the 

 surface of the ice. If this hypothetical coal field were 

 700 miles long by 143 wide, and if the seams were only 

 12 feet thick, there are coal reserves here second only 

 to those of the United States. (See Figure 11.) 



Granites. — We may devote some space to a con- 

 sideration of the eruptive rocks in Victoria Land. 

 There are several types of granite, each associated with 

 various dyke rocks. Gray granite occurs near Mount 

 Larsen (latitude 75° S.) and near the Beardmore Gla- 

 cier. Mawson thinks this is somewhat older than the 

 pink granites, while both are perhaps younger than 

 the diorites and gabbros which occur at intervals along 

 the same coast. Somewhat similar granites and schists 

 characterize Edward VII Land. The gray granites are 

 low in lime and magnesia and high in potash and soda. 

 This chemical composition of the older granites and 

 porphyries is widely different from that of the Pacific 

 type, and is essentially an Atlantic type of rock. So 

 also the dolerites and Kenytes belong to the same gen- 

 eral facies, though the diorites and quartz-dolerites (in 

 David's opinion) have some resemblance to Pacific 

 types of rock. David quotes the following differences 

 as distinctive : 



lOI 



