Thermal stability and oxidation of Mn3O4

Semi-quantitative spectrochemical analyses of the rocks representing the three major lithological units of the Nuggihalli schist belt, namely the ultrabasic rocks, the green schists, and the amphibolites have been done. Based on the distribution of elements like Cr, Ni, Cu, Co, V, Ti and B, the amphibolites of this region are considered to be ortho-amphibolites formed after the pre-existing igneous rocks of doleritic or basaltic composition. Further, by a comparison of the nature of distribution of these elements in the three major rock units, it is inferred that the green schists are derived from the alteration of ultrabasic rock and there has not been any differentiation in the rocks of this region