Glass at endocontacts of granite massifs in Volcanic–Plutonic belts (Exemplified by granite of Central Kazakhstan)

Abstract

Glass formation takes place under conditions of rapid cooling of a melt at a great temperature difference between the melt and the host rock, which must have high thermal conductivity. The most favorable conditions for glass formation exist when the melt intrudes in the form of thin apophyses. Glass has been found in granite massifs related to the volcanic–plutonic association.