Geological structure and material composition of the kimberlite body «Yanvarskoe» (Daldyn-Alakit diamond-bearing district)

Abstract

The new kimberlite pipe «Yanvarskaya» has been discovered in the Alakit-Markha field by a complex of geological and geophysical methods. For its delineation and the study three profile of wells were covered: one profile is along the long axis and two are in the cross stretch at the network 40x40 m. In wells geophysical researches, and also testing works, were carried out, including the selection ot the nine core samples with a total weight of 1120 kg, at the wells which had opened kimberlite. Yanvarskoe kimberlite body has a dike-like form with the orientation of the long axis in a North-East direction (50—55°) with sizes under overlying rocks 90x45 m, with an area of 2836 m2, which allows reference of this body to the class of small bodies. The body is composed of porphyry kimberlites of greenish-gray and yellowish-brown colors, strongly altered, dissected by numerous differently oriented cracks filled with calcite. Based on the results of core testing, a diamond of class -2+1 mm weighing of 2.1 mg (0,01 car.) was found.