Trindade hotspot

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The Trindale hotspot is marked 41 on map.

The Trindade hotspot is a working hypothesis supposing that the submarine volcanic chain Vitória-Trindade, off the eastern coast of Brazil in the southern Atlantic Ocean as a volcanic hotspot chain. It was considered that the supposed hot-spot should be responsible for the creation of the east-west trending Vitória-Trindade seamount chain, which includes the Trindade and Martim Vaz archipelago at its easternmost end. Trindade, a small island in the archipelago, is the hotspot's most recent eruptive center.

This ideas was based on the geochemical data, especially of the highly silica-undersaturated alklaine ultramafic rocks of the Trindade Island and Martim Vaz Island. The isotopic data is OIB-type, which is favourable to the hot-spot hypothesis. However, the volcanic chain direction is E-W and the absolute motion vector of the South America Plate is NW. Therefore, the volcanic chain cannot be a hot-spot chain. Recent research papers, as Skoletnev et al. (2010) and Motoki et al. (2012), proposed that the hot mantle penetrated horizontally along the Vitória-Trindade fracture zone which is present in the lithospheric mantle. Because of the same reason, the Fernando de Noronha Volcanic chain also is not a hot-spot chain. On the other hand, the NW-SE magmatic alignments, such as the Cruzeiro do Sul Chain, Bahia Chain, and Macau-Queimado, are considered to be hot-spot chains.

References[edit]

Motoki, A., Motoki, K.F., Melo, D.P. 2012. Caracterização da morfologia submarina da Cadeia Vitória-Trindade e áreas adjacentes, ES, com base na batimetria predita do TOPO versão 14.1. Revista Brasileira de Geomorfologia, Porto Alegre, 13-2, 151-170. ISSN 2236-5664. http://www.lsie.unb.br/rbg/index.php/rbg/article/view/220/174

Skoletnev, S.G., Peyve, A., Truko, N.N. 2010. New data on the structure of the Vitoria-Trindade seamount chain (western Brazil basin, South Atlantic). Doklady Earth Sciences, 431-2, 435-440. http://link.springer.com/article/10.1134%2FS1028334X10040057?LI=true