INVESTIGADORES
DAHLQUIST Juan Andres
congresos y reuniones científicas
Título:
SEGUNDO REPORTE DE CORDIERITAS RICAS EN Na-Be EN ARGENTINA, SIERRA DE VELASCO.
Autor/es:
DAHLQUIST, J.A.; ALASINO, P.H.
Lugar:
Dpto. de Ciencias Geológicas, Facultad de Cs. Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto.
Reunión:
Congreso; AVANCES EN MINERALOGÍA, METALOGENIA Y PETROLOGÍA 2004; 2004
Institución organizadora:
Dpto. de Geología, Fac. de Cs. Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto. Dpto. de Ciencias Geológicas, Fac. de Cs. Exactas y Naturales, Universidad de Buenos Aires.
Resumen:
ABSTRACT: SECOND REPORT OF Na-Be CORDIERITES IN ARGENTINA, FROM SIERRA DE VELASCO. Na-Be cordierites (Na2O = 15 -1.58% and estimated BeO = 0.92 - 0.94%) occur in peraluminous granitoid outcrops in northeastern sierra de Velasco. This is the second report from Argentina (and probably from world?) of this type of cordierite founded in granitoids. Based on bulk analysis of the cordierite, we provisionally argue that Na and Be were introduced through the substitution 2Na(channel)+2Be(VI-IV) --- Mn(VI)+Si(IV) and propose a way to estimate the Be content in Na-cordierite. The crystallization of Na-Be cordierites would have been supported by the composition of the parental magma, which was derived by melting of metapelites with a distinctive alkali and Be content and lack of cordierite.
