Kimberlites, Lamproites, Lamprophyres, Carbonatites, other Alkaline Rocks, and Mafic Dykes from the Indian Shield: Glimpses of Research (2012-2016)

Abstract

Major highlights of researches carried out on kimberlites, lamproites, lamprophyres, carbonatites, other alkaline rocks and mafic dykes from the Indian shield during 2012-2016 are presented. New findings involving field mapping, petrology, geochemistry (including high quality mineral based in situ isotopic studies) and geophysics have provided remarkable insights on the mode of their occurrence, timing of emplacement, mineralogy and bulk-rock composition, redox conditions, relative contribution of the lithosphere and asthenosphere, as well as their economic potential. Several large-scale geodynamic aspects such as plume-lithosphere interactions, ancient subduction events, layered structure of the sub-continental lithospheric mantle, spatial extent of the Precambrian large igneous provinces and supercontinent configurations could be unraveled from these studies on deep-mantle derived small-volume magmatic rocks.

Mineralogy of the Vattikod lamproite dykes, Ramadugu lamproite field, Nalgonda District, Telangana: A possible expression of ancient subduction-related alkaline magmatism along Eastern Ghats Mobile Belt, India

“…The Dharwar Craton contains numerous kimberlites and lamproites (Neelkantam, 2001; Fareeduddin and Mitchell, 2012; Chalapathi Rao and Srivastava, 2016; Shaikh et al ., 2016). These rocks are disposed almost parallel to the interface of the juxtaposed Eastern Ghats Mobile Belt and the Eastern Dharwar Craton (Fig.…”

“…1; Neelkantam, 2001; Fareeduddin and Mitchell, 2012; Gurmeet Kaur and Mitchell, 2016). The lamproite fields in the Eastern Dharwar Craton are: (1) The P2-West, P12, P5, P13, TK1 and TK4 intrusions of Wajrakarur field; (2) the Chelima, Zangamarajupalle, Garledinne, Banganapalle lamproites of the Cuddapah Basin; (3) the Krishna lamproite field; and (4) the Ramadugu lamproite field (Fareeduddin and Mitchell, 2012; Gurmeet Kaur et al , 2013; Gurmeet Kaur and Mitchell, 2013; Gurmeet Kaur and Mitchell, 2016; Chalapathi Rao and Srivastava, 2016 and references therein; Shaikh et al, 2016). Many of the above rocks were considered previously to be ‘kimberlites’ in previous investigations but are now reclassified as lamproites (see Fareedudddin and Mitchell, 2012 and references therein; Gurmeet Kaur et al , 2013; Gurmeet Kaur and Mitchell, 2013; Gurmeet Kaur and Mitchell, 2016; Shaikh et al ., 2016).…”