New Geological-Industrial Type of Porphyry Gold-Molybdenum Ore Mineralization in the Eastern Transbaikal Region (Exemplified by the Sypchugur Ore Cluster)

摘要

The Sypchugur ore cluster is located in the central part of the Transbaikal region 120 km southeast of Chita, its administrative center, and 50 km away from the nearest Darasun railway station. It is crossed by the Aksha highway, which connect the Darasun station with the Verkhnii Ul'khun Settlement at the Russia-Mongolia border. Systemic investigation of the area in question started in 1951. Subsequently, multiple different-scale geological-geophysical investigations, owing to which the Gorkhonskoe gold-ore deposit was explored in detail, were carried out. They revealed also a stockwork of gold-bearing metasomatites with average gold concentrations of 0.9 and 0.7 g/t at depths of 101 m (Borehole 1) and 97 m (Borehole 2), respectively. In addition, four gold ore occurrences were documented in the Sypchugur ore cluster. Their gold concentrations and reserves remain unrated, since all the works aimed at revealing gold mineralization of the Balei geological-industrial type (low-temperature vein) were unsuccessful. Generalization of the available geological, geochemical, and geophysical material with respect to porphyry copper mineralization accompanied by repeated sampling for gold, copper, and molybdenum in reference areas of the Sypchugur ore cluster allowed its prospects to be revised.