Famatinian granulite facies metamorphism in the central basement domain of the Sierra de San Luis, Eastern Sierras Pampeanas, Argentina.

STEENKEN, A., LÓPEZ DE LUCHI, M.G., SIEGESMUND, S., WEMMER, K

Brasilia, Brasil

Conferencia; Granulite Conference; 2006

Universidad de Brasilia

In the Pringles Metamorphic Complex(PMC) the central basement domain of the Sierra de San Luis (Eastern Sierras Pampeanas), high temperature low/medium pressure (5.7-6.4 kbar/740 celsius degree) granulite facies rocks are spatially associated with a NNE trending belt of mafic?ultramafic intrusions. The metamorphism was generally related to the D2 controlled accommodation of these back-arc mafic and ultramafic melts. The corresponding P?T path displays an anti-clockwise loop, characterised by a prograde evolution with an inferred coeval heating and limited pressure increase and by a retrograde stage with a near isobaric cooling initial phase. A relatively high geothermal gradient (around 40ºC/km) is registered in the complex