FLUID-FLOW DURING CONTACT-METAMORPHISM - PETROGRAPHIC EVIDENCE FROM THE URANIUM PROSPECT AT TUMMALAPALLE IN THE SOUTHWESTERN PART OF CUDDAPAH BASIN, INDIA
Rd. Raju et al., FLUID-FLOW DURING CONTACT-METAMORPHISM - PETROGRAPHIC EVIDENCE FROM THE URANIUM PROSPECT AT TUMMALAPALLE IN THE SOUTHWESTERN PART OF CUDDAPAH BASIN, INDIA, Journal of the Geological Society of India, 45(4), 1995, pp. 439-444
In the uranium prospect at Tummalapalle in the southwestern part of Cu
ddapah basin, fluid flow during contact metamorphism is documented in
a vein-mineral-assemblage of a metadolerite intruding the carbonate ro
cks and shale of the Vempalle Formation of the mid-Proterozoic Lower C
uddapah Supergroup. The minerals in the vein are calcite, quartz, Mg-c
hlorite and Fe-chlorite formed in that order due to fluid-infiltration
-driven volatilization reactions involving CO2- and H2O- fluid having
an external source in the nearby sedimentary rocks. The observed seque
ntial vein-mineral assemblage is considered as a petrographic evidence
of 'infiltrating fluid mechanism during metamorphism', proposed first
by Ferry (1980), as well as for 'batch volatilization' of Valley (198
6).