Planeta Rica, NW Colombiauna ofiolita de zona de supra-subducción del Jurásico Tardío
- C. Ramírez-Cárdenas 1
- M. Weber 1
- M. Tobón 1
- J.A. Proenza 2
- A. Beltrán-Triviño 3
- N. Pujol-Solà 2
- S. Betancur 1
- A. von Quadt 4
- J. Duque 3
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1
Universidad Nacional de Colombia
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2
Universitat de Barcelona
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- 3 Universidad EAFIT, Medellín, Colombia
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4
Swiss Federal Institute of Technology in Zurich
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ISSN: 1576-5172
Ano de publicación: 2021
Título do exemplar: X Congreso Geológico de España
Número: 18
Páxinas: 1059
Tipo: Artigo
Outras publicacións en: Geotemas (Madrid)
Resumo
In northwestern Colombia, Planeta Rica locality, in the core of the San Jacinto Fold Belt, there are outcrops of oceanic palaeolithosphere, where the mantle-crust transition zone (MTZ) is preserved. This MTZ is composed of serpentinites, ser- pentinized lherzolites, plagioclase-impregnated peridotites and chromitites (Planeta Rica Peridotites) and gabbros, horn- blende gabbros and clinopyroxenites (Porvenir Gabbro). Mineral chemistry and whole-rock geochemistry data point to a supra-subduction zone (SSZ) environment and U-Pb zircon dating of the Porvenir Gabbro indicate a Late Jurassic age of crystallization (149.7 ± 1.2 Ma, n = 31). Due to the scarce record of Jurassic oceanic rocks in Colombia, the mantle-crust transition zone (MTZ) found in Planeta Rica is a unique example for understanding the fragmentation of western Pangaea during Jurassic times and the early evolution of the Caribbean.