INGEIS   05370
INSTITUTO DE GEOCRONOLOGIA Y GEOLOGIA ISOTOPICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Mineralogía de thomsonita, Junin de los Andes, Neuquen
Autor/es:
MARIA ELENA VATTUONE; SABRINA CROSTA; BERBEGLIA, YANINA; CARMEN MARTINEZ DOPICO; ERNESTO GALLEGOS
Lugar:
FCEyN-UBA
Reunión:
Congreso; VIII Congreso de Mineralogia y Metalogenia 2006; 2006
Institución organizadora:
Catedras de Mineralogia y Petrologia-FCEyN-UBA
Resumen:
ABSTRACT: An assemblage of thomsonite and natrolite has been found in tertiary amygdaloid basalts of Jun¨ªn de los Andes, Neuqu¨¦n. The thomsonite crystals appear in an intergrowth with natrolite. The physical and optical properties of this thomsonite are: radiated acicular crystals; lenght along c axis, with {100}, {010} and {h0l} forms; straight extintion; 2V¦Ã=45¡ã and weak dispersion r>v ; the orientation is: ¦Á, ¦Ã, ¦Â ¡Ô a,b,c. The XRD shows that a0=13,027, ,b0=13,064 and c0=13,178; Tsi=0.60 and Si/Al=1,48. These parameters are in accord with the ordered variety of thomsonite formed with natrolite in alkaline environment at low temperatures.