Research Projects

The models for occurrence of diamonds suggest that diamonds are formed in the mantle beyond 150 km depth (below graphite-diamond stability field) and are brought to the surface at high speed by kimberlites and lamproites. These are found mostly at contact between the thick and old cratonic root and a relatively thin Proterozoic lithosphere. Thus, such contact zones of contrasting lithospheric thicknesses are promising locales for the occurrence of diamonds. Further, recent studies suggest that diamond formation in the subcontinental lithospheric mantle associate with formation of depleted roots by infiltration of CO2-rich fluids. The Lithospheric structure and extent of Precambrian tectonic entities of the Bundelkhand craton (BKC) are poorly known, though wealth of geological and geochemical information is available. Recent MT investigations in the northern part of the BKC propose the infiltration of fluids from the subducted oceanic slab and metasomatism of the sub-continental lithospheric mantle (SCLM). The well-known potential Panna diamond province with presence of kimberlite/lamproite source rocks, secondary conglomerates, and Quaternary to Recent placer deposits is located at the contact zone of the BKC and the Vindhyan basin. The Majhgawan and Hinota pipes are the main primary conduits for diamonds in addition to few more places around Panna. In 2004, M/s Rio-Tinto Pvt. Ltd. explored the area around Panna and discovered a cluster of eight diamondiferous bodies at Bunder village, district Chhatarpur. The company took up detailed exploration under Bunder Diamond Project and projected a resource of 37 million carat of diamonds at an average grade of 0.7 carat per tonne. This deposit is considered to be seven times richer than the Panna Diamond Mine. Study region and survey plan: The study location lies between contact zone of the Bundelkhand craton and the Vindhyan basin, geographically located Chattarpur and Panna districts, Madya Pradesh. We plan to carry out the survey along three NW-SE profiles spread between Panna and Bunder diamond prospect regions cutting across the contact zone. Among three proposed profiles, Central profile (P1) has 200 km length and other two profiles (P2, P3) are of 25-30 km length each. For the profile P1, we shall acquire broadband MT data at 30 sites with progressively increasing inter-station spacing from 2 km at the contact zone to about 10 km at the two ends of the profile. The profile will also be covered by LMT data at 8 sites at inter-station spacing of about 25 km. For the other two short profiles, we shall aim at 15 broadband MT sites each at the inter-station spacing of about 2 km (Total 30 sites). Objective and expected Derivable:  Lithospheric electrical resistivity architecture of the contact zone between the Bundelkhand craton and the Proterozoic Vindhyan basin between Panna and Bunder  Information on possible linkage between the lithospheric architecture and diamond occurrences