Petrological and geochemical characteristics of the deccan flood basalts (LIP) of Nagpur, India: implications on their genesis

The Late Cretaceous-Early Tertiary Deccan Large Igneous Province (LIP) is one of the largest continental flood basalt provinces on Earth and extends from west coast of India to the area around Nagpur in central India. Here we present comprehensive whole-rock geochemical data (major and trace elements) for the six Deccan basalt lava flows exposed within Nagpur city. The horizontal basalt lava flows are in places separated by the partings of the Intertrappean Beds or red/green ‘bole’ horizons (inter-basaltic weathered material). Petrographically the basalts are either fine grained equigranular or exhibit a microporphyritic texture with plagioclase and olivine occasionally occurring as phenocrysts. Chemically, the basalts are low K, high Ti tholeiites that have a slightly oversaturated quartz normative character. It is concluded that there is definite evidence of the process of differentiation having operated in producing the basaltic lava flows at Nagpur.