Rb-Sr geochronology of the late Archaean-early proterozoic basement granites adjoining the Southwestern margin of the Cuddapah basin

The paper presents Rb-Sr geochronological studies on the granites from two localities, viz, Mulapalli - Lakkireddipalli and Madireddigaripalli, Cuddapah District adjoining southwestern margin of the Cuddapah basin. Earlier geochronological studies indicate that the granites from the adjoining areas to the southwestern margin of Cuddapah basin have ages ranging from 2000-2500 Ma. The present granite bodies are important as they acted (i) as source for the strata bound type of uranium deposit hosted by impure dolostone of Vempalle Formation of the Papaghni Group belonging to the Cuddapah supergroup of rocks, and (ii) as host for the fracture controlled uranium mineralisation in the deformed granite (mylogranite). Isotopic studies were carried out using usual laboratory procedures of Rb-Sr dating