Evolution of a high-grade ductile shear zone through the analysis of textural and compositional changes-an example from the Famatinian orogen, Sierra de La Huerta, San Juan, Argentina.

CASTRO DE MACHUCA, B; DELPINO, S; MOGESSIE, A.; PONTORIERO, S.; PREVILEY, L.; BJERG, E. A.

Rio Cuarto

Taller; XIV Reunion de Tectonica y III Taller de Campo de Tectónica; 2009

Departamento de Geología de la Facultad de Ciencias Exactas, Físico – Químicas y Naturales y la Comisión de Tectónica (ComTec) de la Asociación Geológica Argentina.

A lower granulite to upper amphibolite facies ductile shear zone with NNE trending and E dipping mylonitic foliation has been recognized in the Arenosa Creek, Sierra de La Huerta, province of San Juan, affecting an outcrop of quartzose metagabbro-metadiorite (PI-Hbl-Bt-Qtz±Cpx±Opx-opaques) which is part of the Famatinian magmatic arc of the Western Sierras Pampeanas. Kinematic analysis of the Arenosa Creek Shear Zone (ACSZ) indicates reverse-sense of shear with a minor component of dextral displacement This is compatible with the kinematics of other ductile deformation zones in the area, collectively forming a network. Granulite to upper amphibolite facies ductile shear zone with NNE trending and E dipping mylonitic foliation has been recognized in the Arenosa Creek, Sierra de La Huerta, province of San Juan, affecting an outcrop of quartzose metagabbro-metadiorite (PI-Hbl-Bt-Qtz±Cpx±Opx-opaques) which is part of the Famatinian magmatic arc of the Western Sierras Pampeanas. Kinematic analysis of the Arenosa Creek Shear Zone (ACSZ) indicates reverse-sense of shear with a minor component of dextral displacement This is ompatible with the kinematics of other ductile deformation zones in the area, collectively forming a network. Granulite to upper amphibolite facies ductile shear zone with NNE trending and E dipping mylonitic foliation has been recognized in the Arenosa Creek, Sierra de La Huerta, province of San Juan, affecting an outcrop of quartzose metagabbro-metadiorite (PI-Hbl-Bt-Qtz±Cpx±Opx-opaques) which is part of the Famatinian magmatic arc of the Western Sierras Pampeanas. Kinematic analysis of the Arenosa Creek Shear Zone (ACSZ) indicates reverse-sense of shear with a minor component of dextral displacement This is ompatible with the kinematics of other ductile deformation zones in the area, collectively forming a network.