Two submarine ridges connect New Guinea and North-eastern Australia with the two islands composing New Zealand and appear to show the path of the displacement. They are perhaps molten masses from the underside of the block which have been left behind.
Very little can be said about the connection of Australia to Antarctica, owing to our lack of knowledge of the latter continent. A broad strip of Tertiary deposits follows the whole of the southern margin of Australia and continues through the Bass Straits, after which, however, it is first found again in New Zealand, the east coast of Australia being, however, free therefrom. Perhaps, in the Tertiary, Australia was already separated from Antarctica by a flooded rift-valley, perhaps already (apart from the Tasmanian anchor) even by deep sea. It is generally assumed that the structure of Tasmania is continued into the Antarctic Victoria Land. On the other hand, Wilckens[1] writes: “The south-westerly curve of the mountain system of New Zealand (the so-called Otago saddle) appears to be suddenly cut short on the east coast of South Island. This termination is not natural, but depends without doubt on a fracture. The continuation of the system can only be sought for in one direction, that of the Cordillera of Graham Land, the Antarctic Andes.”
It remains still to be mentioned that the eastern end of the Cape mountains in South Africa also represent a breaking-away. According to our admittedly uncertain reconstruction of the position of Antarctica, we have to seek the continuation of these mountains between Gauszberg and Coats Land, where, however, the coasts are still quite unknown.
The connection of West Antarctica with Patagonia
- ↑ O. Wilckens, “Die Geologie von Neuseeland,” Geol. Rundsch., 82 pp. 143–161, 1917.
