Large igneous provinces – global perspectives and prospects in India

Abstract

The origin and emplacement of Large Igneous Prov-inces (LIPs) is a challenging research frontier in earth sciences that has implications for understanding: (a) the dynamics and evolution of the earth's mantle, (b) atmosphere and climatic shifts, (c) redistribution of land and oceans, (d) biosphere involving transfer and migration of flora and fauna and mass extinc-tions, (e) metallogeny, and (f) source of hydrocarbons. In this review, we appraise contemporary models for the origin of LIPs (plume versus non-plume) to evalu-ate their strengths and limitations. We also examine vexed issues (e.g. nature and extent of mantle hetero-geneity, role of fluids in LIP genesis, relation amongst carbonatites, kimberlites and LIPs, linkage of dyke swarms to LIPs and continental reconstruction and metallogeny) which are not readily explained by any of the models. Pursuable research frontiers in Indian igneous provinces (e.g. identification of new LIPs in the Precambrian, Fe-enrichment, fertility and thermal state of mantle below India, detailed study of lava stratigraphy and palaeomagnetism, assessment of duration of LIP activities, irrespective of composition-al variability) are identified for future study. De- spite large-scale magma generation, crust-mantle interaction and geodynamic evolution of South Asia through the Phanerozoic, research on modern lines on Indian LIPs is limited. Research on LIPs deserves a major thrust in India for better understanding of the evolution of large magmatic provinces in the Peninsu-lar and Extra-Peninsular regions.