open access

https://doi.org/10.14943/lowtemsci.76.243

https://hdl.handle.net/2115/70338

Origin of the Southern Ocean

日本語

plume activity

2018-03-31

低温科学第76巻編集委員会

Low Temperature Science

76

243-258

The Southern Ocean had been formed by the continental break-up of the Gondwana. In this paper, we review the break-up history of the Gondwana to understand the Southern Ocean formation in terms of geology, geophysics, and tectonics. Two cases of continental break-up are proposed: continental break-up followed by plume upwelling or ascending of deep hot materials due to thinning continental lithosphere during continental break-up. In the cases for break-up of the East Gondwana, with which the Southern Ocean was directly formed, it is likely that deep hot materials arose after rifting of the continental lithosphere. The distribution of continent and ocean in the Southern Ocean had completed at around 30 Ma when Antarctica had been isolated near the present location. Tasmanian gateway between Australia and Antarctica had formed at approximately 34 million years ago, and the Drake Passage between South America and Antarctica had formed at approximately 27 million years ago.

紀要論文

Version of Record

1880-7593

AA12122962