Abstract

TORO-TORO, Luz Mary; MORENO-SANCHEZ, Mario; GOMEZ-CRUZ, Arley de Jesús  and  GIRALDO-GARCIA, Juliana. Metagabbros of Gran Roque Island (Venezuela). Geochemistry and petrography. Rev. acad. colomb. cienc. exact. fis. nat. [online]. 2014, vol.38, n.148, pp.312-320. ISSN 0370-3908.

The Gran Roque Island, located in northern Venezuela, is part of the southern Caribbean islands where the basic basement is outcropping. This basement is composed of fine-grained metagabbros, with subophitic relict texture defined by the larger plagioclase laths that enclose the ferromagnesian minerals. The mineral assemblage of chlorite-actinolite-plagioclase-quartz indicates that the rock reached a low metamorphic grade green schist facies. The chemistry of the Gran Roque island metaggabros supports the petrographic identification and characterization. These rocks exhibit tholeiitic affinity and REE flat patterns, which could be correlated to magmas generated at oceanic ridges of N-MORB type

Keywords : Gran Roque; metagabbros; N-MORB; Venezuela.

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