Өндөрцагааны ховор металт грейзен ордын геологи, эрдсийн найрлага

Abstract

Undurtsagaan ore deposit is located within the intrusive dome developed by Berkh fault zone at the northwest area of Devonian overlapped depression called as Kherlen. Geologic setting of the deposit is dominantly characterized by silicified and clay schist, quartz-sericite schist of Tsargiin gol formation and gabbroid and diabase dikes occurring mostly comfortable with the schist but rarely crossing them. The central part of the deposit is intruded by leucogranite stock-like body. As a result, uppermost granite and overlying terrigenous rocks are subjected to a lot of cracks to cause greisen alteration and rare metal ore formation. The rare metal greisen appears as oval-shaped stockwork with NW-extension of 1500m in length and 1000m in width. The veins and veinlets found within the greisen are dominant of quartz-tungsten, quartz-tungsten-molibdenite, and quartz-beryl in composition as well as have great value of extraction. Since the ore forming processes consisted of subsequent events, the ore is very complex in composition. According to the result of mineragraphic and petrographic analysis, there are identified approximately 70 minerals mostly including W, Mo and Be. No survey into the depth has been conducted, yet. W and Mo reserves might be increased by further detailed exploration.