Zonalidad composicional en anfíboles de las zonas de reacción entre cuerpos ultramáficos y la roca de caja metasedimentaria del complejo Guarguaráz, Cordillera Frontal de Mendoza, Argentina.

GARGIULO, M. F.; BJERG, E. A.; MOGESSIE, A

Río Cuarto

Congreso; MINMET 2010; 2010

AMA y UNRC

This contribution shows the characteristics of zoned amphiboles crystallized in reaction zones developed between ultramafic bodies of Las Tunas Mafic-Ultramafic Belt and the metasedimentary basement of the Guarguaráz Complex, outcroping in the eastern side of the Guarguaráz Range in Frontal Cordillera. The study area belongs to the Salamanca copper district located at 30 km WSW from the Tupungato village, in Mendoza province of Argentina. The petrographic and mineralogical study of representative samples from this area were complemented with electron-microprobe analyses which allowed us to identify and classify the minerals present in these rocks but also to define the crystallization sequences of different mineral associations. With this information we were able to discriminate the events and the evolution of the processes that have affected these rocks. In the area, strongly serpentinized ultramafic bodies related to fault zones crop out. The most important mineral paragenesis of economic interest in this area is talc + amphibole + chlorite. In some places, talc zone near the ultramafic unit is followed by an amphibole zone and then a chlorite zone near the mica-schist. In all cases, these zones are transitional between them. The data presented in this contribution deals with the characteristics of zoned amphibole crystals developed in the transition zone between the amphibole and the chlorite zones and its geological implications.