Investigation and assessment of silica in NW of Argentina

GARCÍA MATÍAS; AVILA JULIO; LAZARTE JOSÉ; MAS, GRACIELA; BENGOCHEA, LEANDRO

Mine Planning and Equipment Selection 2007

Singhal, Fytas, Jongsiri & Ge

Lugar: Bangkok; Año: 2007; p. 49 - 58

Abstract This paper deals about geological investigation of silica deposit in NW of Argentina. The studied area is located in the western flank of Sierra de Ambato, Catamarca, belongs Sierras Pampeanas Occidentales morphostructural province. The oldest rocks are metamorphites of Precambrian – Eocambrian age intruded by a granitic stock of Paleozoic age. Seated in both formation the quartz body has N-S strike and 10 km length with thickness up to 1,2 km . The body is compound mainly of quartz with very small quantities of muscovite, feldspar and clays. A high fracturing degree is observed in all its extension. Microscopic, X rays and chemical determinations indicates that the fine fraction corresponds mainly to quartz. Early and late fluid inclusions were defined. There is a width range between 120ºC and 360ºC . It is proposed that the body was formed during the hydrothermal stage genetically linked to magmatic intrusion. The quartz body has been discontinuous exploited in different sectors from half of last century. Mining has been developed mainly open cast. Nowadays there is not mining activity in the area The mining district, that has geologic reserves of around 1500 million tons with contents in silica upper to 95%, is considered one of the most important of this type in the NW of Argentina