OCCURRENCE OF ULTRAMAFICS OF KOMATIITIC AFFINITY IN THE RIKHABDEV-DUNGARPUR BELT, UDAIPUR AND DUNGARPUR DISTRICTS, RAJASTHAN

Preliminary study of the ultramafic suite of rocks emplaced concordant ly in the Proterozoic supracrustals of the southern Rajasthan (Aravall i Supergroup) indicates their komatiitic nature. Though the diagnostic spinifex texture is not observed in the highly serpentinised and meta morphosed ultramafics, the amygdaloidal structure and the previously r eported igneous joints provide textural evidences for the extrusion of the ultramafic lava. The altered ultramafics still retain certain che mical signatures (high MgO and Mg- No., Low TiO2, Al2O3 and alkalis)of standard komatiites.