GEOLOGICAL RELATIONSHIP WITH NEIGHBOURING COxNTINENTS S99 



from west to east. Beds containing a rich Jurassic flora at Hope Bay rest on 

 coarse conglomerates, which in turn repose on current-bedded sandstone with obscure 

 plant remains. Cretaceous rocks, containing an abundant marine fauna, are 

 followed by Oligocene or Miocene strata, partly marine, partly freshwater or 

 estuarine, the probable equivalent of the Patagonian Molasse of Wilckens. A 

 basaltic series follows, capped by the " pecten conglomerate," considered by J. Gunnar 

 Andersson to be the equivalent of the Parana beds of Cape Fairweather. In addition 

 to these stratified rocks, the American Sector of Antarctica exhibits intrusive gabbros 

 and granodiorites of most characteristic Andean affinities. AMiile the relation of 

 the American Sector of Antarctica to South America is thus extremely obvious, the 

 problems presented by the great ranges of South Victoria Land are very perplexing, 

 for while the fracture lines of the Andes appear to invade this region and to dominate 

 its topography, all trace of Post-Mesozoic folding, so characteristic of the American 

 Andes, is absent from the ranges of South Victoria Land, as far as is known at 

 present. Petrologically also the South Victoria Land region differs almost wholly 

 from the Andean type. The latter is of course typically of Pacific type, while the 

 former is of Atlantic type. The relation of the ranges of South Victoria Land 

 to the trend lines of the Andes on the one hand, and to those of Australasia, 

 especially New Zealand, on the other, is one of the most interesting, and at the 

 same time perhaps one of the most difficult of the tectonic problems presented to 

 modern geology, and all we can presume to do under the circumstances is to offer 

 a few suggestions very tentatively, referring readers to Suess' masterly summary 

 {op. cit.,' vol. iv.) for what is known about the relations of the South American 

 and Patagonian Andes to the mountains of the American Sector of Antarctica, 

 and to the original works of such writers as T. P. Moreno, R. Hawthal, 0. 

 Nordenskjcild, J. G. Andersson, O. Wilckens, H. Aretowski, E. Gourdon, C. Darwin, 

 C. Burckhardt, J. B. Hatcher, S. Roth, L. Weirli, H. Steften, G. Steinmann, 

 Dr. Hyades, A. Reiter, Fonck, Halle, J. B. Scrivenor, and many others, references 

 to whose works are given by Suess. 



The following are the chief factors which may be erajJoyed in the correlation 

 of the Antarctic regions with adjacent areas of the earth : — 



1. The tectonic structure in reference to the chief earth trend lines. 



2. The petrographical character of the eruptive rocks. 



3. The i^aleeontological evidence afforded by the fossil fauna and flora. 



1. The Tectonic Structure in Reference to the Cldcf Earth Tre^id Lines. 

 In the chapter of this Memoir dealing with the physiography of the Antarctic, 

 reference has already been made to the existence of the great horst, bounded by 

 very heavy faults. This horst was proved by our expedition to extend from near 

 Cape Adare for about 1000 statute miles, first south then south-east, far beyond 

 the upper end of the Beardmore Glacier. On his recent brilliant march from the 



