Paraná and Etendeka traps

A cliff at the Paraná Magmatic Province. Rio do Rastro, Santa Catarina. One can see the near vertical escarpment of silicic succession from waning-stage volcanism.

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 (580,000 miles²) and an original volume projected to be in excess of 2.3 x 106 km³.[1][2]

The basalt samples at Paraná and Etendeka have an age of about 132 Ma.[3] 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[4][5] and in 2013 were assessed as being part of the traps system following recovery of samples.[6] 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).[7]

See also

References

  1. Courtillot, Vincent E.; Renneb, Paul R. (January 2003). "Sur l'âge des trapps basaltiques (On the ages of flood basalt events)". Comptes Rendus Geoscience 335 (1): 113–140. doi:10.1016/S1631-0713(03)00006-3.
  2. Fodor, R.V.; McKee, E.H.; Roisenberg, A. (1989). "Age distribution of Serra Geral (Paraná) flood basalts, southern Brazil". Journal of South American Earth Sciences 2 (4): 343–349. Bibcode:1989JSAES...2..343F. doi:10.1016/0895-9811(89)90012-6.
  3. SUBSCRIPTION REQUIRED; 3-D, 40Ar-39Ar geochronology in the Paraná continental flood basalt province
  4. O'Neill, C.; Müller, R. D.; Steinberger, B. (2003). "Revised Indian plate rotations based on the motion of Indian Ocean hotspots" (PDF). Earth and Planetary Science Letters 215: 151–168. Bibcode:2003E&PSL.215..151O. doi:10.1016/S0012-821X(03)00368-6.
  5. O'Connor, J. M.; le Roex, A. P. (1992). "South Atlantic hot spot-plume systems. 1: Distribution of volcanism in time and space". Earth and Planetary Science Letters 113: 343–364. Bibcode:1992E&PSL.113..343O. doi:10.1016/0012-821X(92)90138-L.
  6. 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
  7. Scott E. Bryan; Ingrid Ukstins Peate, David W. Peate, Stephen Self, Dougal A. Jerram, Michael R. Mawby, J.S. Marsh, Jodie A. Miller (2010). "The largest volcanic eruptions on Earth". Earth-Science Reviews 102: 207. doi:10.1016/j.earscirev.2010.07.001. Cite uses deprecated parameter |coauthors= (help);

External links


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