Research Projects

The granitoids of the Banded Gneissic Complex (BGC) occurring in the central Rajasthan are diverse in composition, texture and possibly also in geodynamic setting which might have taken place in different times. They exhibit diverse and complex relationships with the supracrustal sequences. At least three rock associations can be discerned: (1) the granitoids in the Ajmer-Anasagar-Beawar region are a megacrystic variety hosting xenoliths of overlying supracrustal sequence; the granitoids have no intrusive or unconformable relations with the overlying supracrustal sequence. These granitoids have a deceptive basement-cover relationship with the overlying sequence. Lack of clear-cut intrusive relationship or unconformable relationship and presence of xenoliths of the overlying sequence make the scenario very interesting; (2) granitoids in the sandmata-Bhandanwara-Bhinai area are both opx-bearing and biotite-bearing bodies with megacrystic and non-megacrystic textural variants. These are intrusive into the sanmata granulites; (3) the third variety of granitoids occur in Darwal-Amet-Anjana-Gudawali-Masuda area as intrusive bodies into orthogneisses, and as basement to the supracrustal sequence. such diverse and complex geological occurrences of the granitoids have resulted in equivocal stratigraphic status of this terrain. The age of these granitoids are not well constrained. Whole rock major and trace element and isotopic data of these granitoids are also lacking. As a result, the origin, geodynamic setting and crustal evolution history of the BGC of central Rajasthan have remained obscured. All the granitoids host a number of enclaves including mafic magmatic enclaves (MME). This proposal envisages to carry out robust U-Pb zircon geochronology, whole rocks major and trace element and Nd-sr isotopic studies of the granitoids and the MME with a view to understand sources, processes, geodynamic setting and crustal evolution history of the terrain with particular reference to juvenile versus reworking processes, and the role of mafic magma in the evolution of the granitoids. The study will also shed light on basement-cover relationship of the BGC of central Rajasthan.