Shackleton Fracture Zone: no barrier to early circumpolar ocean circulation
Livermore, Roy; Eagles, Graeme; Morris, Peter; Maldonado, Andres. 2004 Shackleton Fracture Zone: no barrier to early circumpolar ocean circulation. Geology, 32 (9). 797-800. 10.1130/G20537.1Full text not available from this repository.
The opening of Southern Ocean gateways was critical to the formation of the Antarctic Circumpolar Current and may have led to Cenozoic global cooling and Antarctic glaciation. Drake Passage was probably the final barrier to deep circumpolar ocean currents, but the timing of opening is unclear, because the Shackleton Fracture Zone could have blocked the gateway until the early Miocene. Geophysical and geochemical evidence presented here suggests that the Shackleton Fracture Zone is an oceanic transverse ridge, formed by uplift related to compression across the fracture zone since ca. 8 Ma. Hence, there was formerly (i.e., in the Miocene) no barrier to deep circulation through Drake Passage, and a deep-water connection between the Pacific and Atlantic Oceans was probably established soon after spreading began in Drake Passage during the early Oligocene.
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Antarctica in the Dynamic Global Plate System|
|NORA Subject Terms:||Marine Sciences
Meteorology and Climatology
|Date made live:||20 Jan 2012 11:38|
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