Early Cretaceous Greater Kerguelen Large Igneous Province and its plumbing systems: A contemplation on concurrent magmatic records of the eastern Indian Shield and adjoining regions

Abstract

A detailed contemplation is attempted to comprehend the likely connection of a large number of Early Cretaceous mafic, felsic, alkaline (kimberlite, lamproites, ultramafic lamprophyre, etc.), and carbonatite magmatic records of the eastern and north‐eastern region of the Indian Shield and adjoining regions. All these Early Cretaceous magmatic records occupied a large area, covering adjoining regions of south‐eastern Tibet, eastern and north‐eastern India, western Australia, Eastern Indian Ocean, southern Kerguelen Plateau, and north‐eastern Antarctica, are supposed to be part of the Greater Kerguelen Large Igneous Province (LIP) and likely to be related to the break‐up of East Gondwana. Available age results, chiefly ranging from ca. 145 to 100 Ma, support a genetic connection with the Kerguelen mantle plume. However, there are other lines of evidences, particularly radiogenic isotope data that preclude direct involvement of any mantle plume component; likely to be derived from decompression melting related to passive rifting. Two major magmatic phases, ca. 145–130 Ma and ca. 124–100 Ma, have been distinctly identified, which could be related to distinct rifting events. Break‐up of East Gondwana had happened at ca. 137 Ma with separation of Western Australia from Greater India. Later, ca. 124–122 Ma, separation of Antarctica from Eastern India occurred. The later magmatic phases (after ca. 120 Ma) are likely to have an indirect connection with the Greater Kerguelen LIP probably with the mantle plume providing extra heat for melting.