Abstract

ESPINOSA-BORGES, Angel Eduardo et al. Petrographic characterization of a metamorphosed rocks sequence from Calentura Arriba (Moa). Min. Geol. [online]. 2023, vol.39, n.2, pp. 88-107.  Epub June 30, 2023. ISSN 1993-8012.

The petrographic characterization of ophiolitic sequence and metamorphized rocks of Calentura Arriba sector in Moa municipality, constitutes a contribution to the updating of the geological map of the southwestern part of cartographic sheet 5277-IV “Moa”. Thin sections of those rocks were analyzed using a polarized light microscope. The ore paragenesis composed of enstatites + augite + labradorite + olivine + chlorite + garnierite + actinolite + tremolite + ilmenite + magnetite + sericite + saussurite in the metagabbro sequence was identified as well as the mineral paragenesis composed of olivine + orthopyroxenes + bastite + lizardite + chrysotile + actinolite + tremolite + antigorite + serpophite + chromite + magnetite in the serpentinite sequence. This sector was subjected to strong transformation processes reflected in the intense alterations that denote the occurrence of low-grade to high-grade metamorphism, matching with the Barrowian facies series. The metamorphic transformations are closely related to the activity of the Moa Fault and denote a regional character, extending at both ends of this fracture.

Keywords : petrography; metamorphosed rocks; ophiolites; Moa.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )