#lunarbasalts

Role of liquid immiscibility has immense importance in petro genesis of basaltic magmas. Roedder, Weiblen [1,2] postulated that high silica and high iron glasses of the lunar basaltic rocks have widespread petro genetic significance. In lunar basalts, generally, the globules of dark brown glass appear to have composition equivalent to Pyroxene + Iron ore. On the contrary, it is significant that Washington [3] initially recognized that the residual glass in the Deccan Trap basalts should be composition corresponding to a mixture of augite and magnetite. The role of liquid immiscibility in basaltic magmas had been graphically depicted by Roedder in terms of SiO2-(FeO+MgO+CaO)-(K2O+Na2O+Al2O3) diagram; characteristically the liquid immiscibility field in Roedder's ternary plot assumes an elongated elliptical geometry relatively away from SiO2-rich corner.The compositions of terrestrial basalts like Deccan Trap [3] Palisade diabase sill etc.