Autopsy on a dead spreading center: The Phoenix Ridge, Drake Passage, Antarctica
Livermore, Roy; Balanyá, Juan Carlos; Maldonado, Andrés; Martínez, José Miguel; Rodríguez-Fernández, José; Sanz de Galdeano, Carlos; Zaldívar, Jesús Galindo; Jabaloy, Antonio; Barnolas, Antonio; Somoza, Luis; Hernández-Molina, Javier; Suriñach, Emma; Viseras, César. 2000 Autopsy on a dead spreading center: The Phoenix Ridge, Drake Passage, Antarctica. Geology, 28 (7). 607-610. 10.1130/0091-7613(2000)28<607:AOADSC>2.0.CO;2Full text not available from this repository.
New bathymetric and magnetic anomaly data from the Phoenix Ridge, Antarctica, show that extinction of all three remaining segments occurred at the time of magnetic chron C2A (3.3 ± 0.2 Ma), synchronous with a ridge-trench collision south of the Hero Fracture Zone. This implies that the ultimate cause of extinction was a change in plate boundary forces occasioned by this collision. Spreading rates slowed abruptly at the time of chron C4 (7.8 ± 0.3 Ma), probably as a result of extinction of the West Scotia Ridge, which would have led to an increase in slip rate and transpressional stress across the Shackleton Fracture Zone. Spectacular, high-relief ridges flanking the extinct spreading center, mapped for the first time using multibeam swath bathymetry, are interpreted as a consequence of a reduction in spreading rate, involving a temporary magma oversupply immediately prior to extinction.
|Programmes:||BAS Programmes > Pre 2000 programme|
|Additional Keywords:||Drake Passage, Phoenix, Antarctic plate, spreading centers|
|Date made live:||29 Nov 2012 09:36|
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