A Method of Delineation of Diamondiferous Fields with Application of GIS-Technology (in the Case of Yakut Diamondiferous Province)

Abstract

The basic principles of mineragenic zoning of the Yakut Diamondiferous Province which have been formed for 60 years of search, prospecting and exploration works on the territory of Western Yakutia are briefly reviewed. The taxonomic range of diamondiferous objects («province», «subprovince», «district», «field», «pipe») is considered. It is shown that separation of boundaries of such objects as «kimberlite field» and «diamondiferous district» often has a subjective character. The difficulties of transition from analog to digital geological materials are reflected through demonstration of the boundaries of a diamondiferous dis- trict and a kimberlite field determined by different authors on digital maps in relevant geographical coordi- nates. The results of forming of digital data base of essential kimberlite bodies parameters such as geograph- ic location, morphology, axes orientation, age (relative and absolute), petrological and mineralogical peculi- arities for each kimberlite pipe or vein of Yakut Diamondiferous Province are present. Practical application of the base for cartographic representation are demonstrated. The method of delineation of a taxonomic unit «kimberlite field» using «buffering method» with application of GIS-technology is presented. It is shown that the most correctly a kimberlite field boundaries are defined by a five kilometers buffering zone which coin- cides with the boundaries of the maximum density of faults and geophysical anomalies. The application of the method allowed to reduce a field area and clarify a direction of a main axis for some kimberlite fields. The proposed method is deployed and operated by PJSC ALROSA geological exploration complex.