Caracterización petrológica de milonitas derivadas de mármoles inmersas dentro de la faja de cizalla Las Lajas, Sierra de Comechingones, provincia de Córdoba.

CRISTOFOLINI E; BENITO P; TIBALDI A

Cordoba

Congreso; XIII Congreso de Mineralogía, Petrología Ígnea y Metamórfica, y Metalogenia.; 2019

In this research, we present a petrological characterization of the marble mylonites identified within the Las Lajas shear zone, in the southernmost portion of the Sierra de Comechingones. Marble mylonites are recognizable in outcrop by their grey to white color and by their anastomoses bands with S-C structure. In thin section, this mylonites exhibits a porphyroclastic texture with a small to medium grained matrix that shows a granoblastic texture of calcite/dolomite, quartz, phlogopite, tremolite, brucite, talc and opaques minerals. In this matrix, monomineralic or polimineralic porphyroclasts of calcite/dolomite, brucite, quartz, diopside and opaques minerals are preserved. Based on the paragenetic associations and the calcite twins observed in the studied rocks, we suggest that Las Lajas shear zone evolved from amphibolite to sub-greenschist facies.