Multivariate Statistical Analyses of Polyphase Igneous Rocks of the Malani Igneous Province with Special Reference to Sarno - Dandali Area, Western Rajasthan

Applying multivariate Linear Regression and Principal Component analyses, the petrogenetic aspects of the polyphase igneous rocks of the Malani Igneous Province, Western Rajasthan were dealt with and inferences arrived. The various rocks of the province belong to different magmatic activities unrelated to each other. Normal and peralkaline rhyolites of the province are not co-genetic. Siwana and Jalor granites are distinct and generated at different stages. The acid dykes represent the end phases of the Jalor granite activity, crystallising from the same melt. Fractional crystallisation has played a major role in the development of the mildly alkaline and hyperalkaline rock series. Pyroxene, iron oxide minerals, feldspathoid and alkali feldspar play a major role in the development of the alkaline rocks, whereas pyroxene, iron oxide minerals and plagioclase playa dominant role in the development of the mildly alkaline rocks. The rocks of different groups fall on different liquid lines of descent in the Latent vector variation diagrams.