Las albititas del Paleozoico Inferior del occidente de Asturias: ¿posible fuente de leucogranitos?

Abstract

In the West Asturian-Leonese Zone there are some albititic beds of volcanoclastic origin interlayered in the lower part of the Serie de los Cabos, deposited in a graben-type basin during the Middle Cambrian. The mineralogy is plagioclase (albite), rutile, sheet silicates and sometimes quartz, carbonates and chloriteserpentine cryptocrystalline masses. Melting experiments at 850ºC, 6 kbar and added 10% water conditions produce very silicic melts, with different rates of melting according to quartz percentage, but the fertility of these rocks as sources of leucogranites is very low