GEOLOGICAL PROBLEMS OF ANTARCTICA 

 R. E. Priestley and C. E. Tilley 



Present Status of Geological Knowledge of Antarctica 



Isolated from the other great land masses of the globe, the Ant- 

 arctic Continent is almost completely encompassed by a broad girdle 

 of deep ocean: Considered as a single unit, it is estimated to possess 

 an area of roughly 5,000,000 square miles, of which the greater part 

 is a plateau covered by ice of great thickness. Of its coast line, only 

 that portion comprised within the Australian Quadrant^ and a small 

 arc of the American Quadrant can be said to be moderately well 

 known. The coasts of the African and Pacific Quadrants are almost 

 completely unknown. Of the interior, beyond the field of view opened 

 up by the traverses to the south magnetic pole and a western traverse 

 from McMurdo Sound by Scott in 1903, only the region in the imme- 

 diate vicinity of the converging lines of the Shackleton, Scott, and 

 Amundsen routes to the pole has been under direct observation. 



Unusual Depth of Antarctic Continental Shelf 



The available bathymetrical surveys of the waters fringing the 

 ice barrier indicate that Antarctica is singular among the continents 

 in the depth of its continental shelf, which is approximately 200 fath- 

 oms below sea level. This can be well illustrated by the following 

 soundings taken by various expeditions. 



Belgica 

 Gauss . . 

 Scotia . . 

 Deuischland 

 Endurance 



Sounding on 

 Shelf (fathoms) 



279 

 209 

 159 

 305 



185 



Sounding in Deep 

 Water (fathoms) 



1476 

 1267 

 1950 

 820 

 1 146 



Distance 

 Apart in 

 Sea Miles 



25 

 18 



45 

 18 



Slope 



I in 21 

 I in 17 

 I in 25 

 I in 35 



Not comparable because 

 oblique 



It is possible, as Nordenskjold and others have pointed out, that 

 the chief factor in determining this abnormal submergence of the 



1 Antarctica may be conveniently considered as divided into four quadrants commencing from 

 the meridian of Greenwich, each quadrant being named after the lands or sea to the north; thus: 

 the African Quadrant, the Australian Quadrant, the Pacific Quadrant, and the American Quadrant. 



