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The Paraná-Etendeka traps (or Paraná and Etendeka Plateau; or Paraná and Etendeka Province) comprise a large igneous province which includes both the main Paraná traps (in Paraná Basin, a South American geological basin) as well as the smaller severed portions of the flood basalts at the Etendeka traps (in northwest Namibia and southwest Angola). The original basalt flows occurred 128 to 138 million years ago. The province had a post-flow surface area of 1.5 x 106 km² and an original volume projected to be in excess of 2.3 x 106 km³. The basalt samples at Paraná and Etendeka have an age of about 132 Ma.〔(SUBSCRIPTION REQUIRED; 3-D, 40Ar-39Ar geochronology in the Paraná continental flood basalt province )〕 Indirectly, the rifting and extension are probably the origin of the Paraná and Etendeka traps and it could be the origin of the Gough and Tristan da Cunha Islands as well, as they are connected by the Walvis Ridge (Gough/Tristan hotspot). The seamounts of the Rio Grande Rise (25°S to 35°S) go eastwards from the Paraná side and in 2013 were assessed as being part of the traps system following recovery of samples.〔(Brazilian 'Atlantis' found - Geologists have announced the discovery of what has been dubbed the 'Brazilian Atlantis', some 900 miles from Rio. ), Donna Bowater, ''The Daily Telegraph'', 7 May 2013〕 Sources are still unclear, however, as to whether this site has been the subject of what may have been the single largest explosive volcanic eruption in Earth's history (see List of largest volcanic eruptions). ==See also== * Geology of Paraguay * Geology of Uruguay * Paraná Basin 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paraná and Etendeka traps」の詳細全文を読む スポンサード リンク
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