On the Myrmekites from the Granite Gneiss of Doranda, Hazaribagh District, Bihar

Abstract

The abundance of myrmekite within the granite gneisses of Doranda is strongly correlated to the proportion of K-feldspar within the granite gneiss. The proportion of quartz in myrmekite is independent of the anorthite content of the myrmekitic plagioclase. These myrmekites have originated due to crystallization of residual liquid within some strain features developed within the plagioclases at their contact with K-feldspar. The strain features resulted due to lateral Stress exerted on the plagioclase by the growing adjacent K-feldspar.