Development of kimberlite exploration Geographic Information System Mohan Singh Khatediya* and Pramod. K. Verma School of Studies in Geology, Vikram University Ujjain-456010, India Tel. 91-0734-511118, Fax 91-0734-514276 drpkverma@rediffmail.com *Department of Geology & Mines, Government of Madhya Pradesh, Bhopal Abstract The Bastar craton (Chattisgarh State) is rich in mineral deposits including diamondiferous kimberlite rocks. The kimberlite occurrences have been reported from different parts of the bastar craton including Mainpur-Deobhog Area (MDA) in Raipur district. As a rule, the kimberlites occur in clusters and hence, arises the need for strategic exploration guide for the kimberlites. Integration of available background information (viz. geology, tectonics, geochronology, rock chemistry etc.) in GIS environment leads to development of Kimberlite Exploration Geographic Information System (KEGIS). The KEGIS paves the way for further kimberlite exploration programme. Introduction The exploration of Kimberlite has an inherent meaning - "exploration for diamond". The Kimberlite exploration involves very risk, which when successful, returns very high rewards. One of the major guideline for Kimberlite exploration is sound understanding of tectonic control on evolution, emplacement and preservation of kimberlite. The fundamental requirement for diamondiferous Kimberlite occurrence is a persistently low geothermal gradient with little thermal erosion as the plume events may destroy the diamond potential of post plume Kimberlite magmatism. The formation and ascent of kimberlite is speculative, however, lithospheric extension is considered to be the main cause for trigger of Kimberlite magmatism. As a rule (Cliford 1966), the kimberlite is found in clusters, fields and provinces exclusive within thick Archaean cratons and immediately adjacent to Proterozoic mobile belt. An especially favourable environment for preservation of kimberlite diatrems is a craton covered by relatively undeformed sedimentary rocks. The exhumation and/or deep erosion of craton leaves behind the root zones of kimberlite diatrems and hypabyssal feeder dykes. Often, kimberlite occurrences indicate distinct alignment with local fault and dyke systems and are related to frequently reactivated regional lineaments (White et al 1995; Smirnov 1993). Any successful prognostic map of kimberlite country takes into account, available regional geological and geophysical maps, remotely sensed data products, indicator mineral occurrences, alkaline mafic rock occurrences, presence of high permeability zones, characteristics of craton and mobile belts, presence of sedimentary cover on craton etc. Exploration guide for kimberlite The first and foremost exploration guide for Kimberlite is the known occurrence of Kimberlite. Once a Kimberlite occurrence is located in any area, the next essential factor for exploration becomes the establishment of regional and local structural control on the emplacement of kimberlite. This task is best achieved through remote sensing techniques supplemented with ancillary data. In Mainpur-Deobhog Area (MDA, Raipur district, Chattisgarh, Fig. 1) there are four known occurrences of kimberlite. Thus, search for new kimberlite occurrence in this area is practically reduced to application of remote sensing technique in understanding the tectonic setting of kimberlite emplacement. The exploration strategy for kimberlite is best achieved through development of GIS with available background information.  Fig. 1. Location map of Mainpur-Deobhog Area
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