Petrography composion and ore-bearing of ultrabasits from the South-Bilozersky massif of the Middle-Dniprean mega-block of the Ukrainian shield

Abstract

Purpose. To determine the matter composition, formational types and degree of hydrothermal-metasomatic alterations of the ultramafic rocks from the South-Bilozersky massif and substantiate the prospects for the ore potential of geological formations. Methods. To accomplish the tasks set, traditional methods of studying the matter composition of rocks and ores, such as petrographic, mineragraphic, were used, the results of chemical, X-ray diffraction, semi-quantitative spectral and thermal analyzes were interpreted. To determine the prospects of ore-bearing, ore-formation analysis and a comparative geological method were used.The use of a complex of modern methods and the interpretation of the research results made it possible to substantiate the ore-formational types of associated raw materials. Findings. The features of the matter composition, internal structure and ore content of the s South-Bilozersky serpentinite massif are characterized and the genetic relationship with the known differentiated basic-hyperbasite massifs of the Bushveld, Stillwater, Duluth, Big Zimbabwe dyke types is substantiated. The presence of cumulative dunites and peridotites within the South-Bilozersky massif suggests their intrusive origin from a deeper source with chamber differentiation. The prospects for the discovery within the South-Bilozersky massif of a medium-sized deposit of talc-magnesite, easily accessible for development in the conditions of the infrastructure of the iron ore plant, are substantiated. The affiliation of talc-magnesite ore occurrences to the hydrothermal-metasomatic formation of listvenites, which were formed during the active introduction of silica and carbon dioxide into the high-magnesian environment of deformed serpentinites, is substantiated. The originality. For the first time, the dislocation-metamorphic genesis of hydrothermal ore-bearing formations within the South-Bilozersky ultramafic massif was substantiated and the influence of the degree of hydrothermal alterations on the quality and degree of preservation of ore formations was shown. Practical implementation. The prospects for ore occurrences of minerals accompanying iron deposits in the Belozerskaya greenstone structure are substantiated, which will make it possible to implement an integrated approach to the development of the bowels of the traditionally iron ore region.