Petrología de las unidades metamórficas e ígneas de las Cumbres del Perchel, Sierras Pampeanas Orientales (Córdoba, Argentina).

SEBASTIÁN OSVALDO VERDECCHIA; MARÍA PÍA SANTOLAYA; JUAN ALBERTO MURRA

San Miguel de Tucumán

Congreso; 20º Congreso Geológico Argentino; 2017

Asociacíon Geologica Argentina

The igneous rocks (peraluminous sieno/monzogranites)are located in the eastern sector of the Cumbres del Perchel (south of theSierra de Cuniputo-Totoralejo), and they intrude the La Falda MetamorphicComplex, which is composed of stromatic migmatite, orthogneisses andamphibolites. Both the igneous and metamorphic units are affected by theCuniputo Deformation Belt, which has been interpreted as inverse cinematic witha sinistral component. The tectono-metamorphic evolution of the sector would begiven by: pre-M1-D1 event, interpreted from the migmatitegarnet cores with oriented inclusions of biotite, quartz and opaque minerals (Sinner),followed by the main metamorphic event that generates anatexis in the stromaticmigmatite (M1), associated to a deformation stage D1-S1,with P-T conditions = 5.9 kbar and711-712 ºC. Subsequently a decompression and cooling stage is recorded, with P-T conditions = 4.7-4.9 kbar and656-672 °C. These units are affected by a deformation stage D2 withabsence of associated mineral blastesis and responsible for a geometricfoliation S2. Finally, a dynamic metamorphic event (M2),linked to the Cuniputo Deformation Belt, is generated, development a Smy(D3) mylonite foliation, subparallel to S1, under P-T conditions = 2.8 kbar and 591 ºC.The age of this deformation belt would be restricted to the Ordovician (~ 447Ma) which suggests that it was part of the deformation of the foreland of theFamatinian orogen.