Tectonostratigraphic Status of the Proterozoic Babarmal Pink Marble from the Aravalli Supergroup

Abstract

Abstract Present study reviews the tectono-stratigraphic status of Babarmal pink marble from the Aravalli Supergroup through mapping and petrographic study of marble as well as associated lithologies. The pink marble is predominantly calcitic and characteristically different from dolomitic carbonate rocks of the Jhamarkotra Formation, the Lower Aravalli Group. The marble is devoid of organic matter and phosphate content unlike the Jhamarkotra dolomite. The pink marble is underlain by quartz-pebble rich conglomerate. This assemblage represents a rare lithological association which has not been reported so far from the Aravalli Supergroup. Besides the above differences between the Babarmal pink marble and the Jhamarkotra dolomite we also noted significant similarities between the two with respect to greenschist facies metamorphism and three phases of deformational history. Similarities in both these aspects imply that the pink marble like the Jhamarkotra dolomite can be corroborated with the Aravalli orogenic cycle. While on the basis of distinguishing lithological and petrographic features the pink marble-pebbly conglomerate, the lithoassemblage is suggested to be designated as “Babarmal Formation” as a modification to the Babarmal Formation of Gupta et al. (1997) which constituted of pink marble. The outcrop patterns on the high resolution map shows that the Babarmal litho-assemblages are sandwiched between the Barytes bearing meta-volcanics (that represent the underlying Delwara Formation) and the dolomite-quartzite-phyllite (that represent the overlying Jhamarkotra Formation) of the Lower Aravalli Group (Roy and Jakhar, 2002). Hence we suggest to place the Babarmal Formation as the middle stratigraphic unit of the Lower Aravalli Group of the Aravalli Supergroup.