The Suzdal gold-sulfide deposit in the black shale of Eastern Kazakhstan

Abstract

The Suzdal gold-sulfide deposit is situated in the northwestern part of the West Kalba gold belt in Eastern Kazakhstan and belongs to the genetic type of stringer-disseminated mineralized zones hosted in the Lower Carboniferous black-shale volcanic-carbonate-terrigenous sequences. Mineralization is controlled by the NE-trending Suzdal Fault. In the north, the deposit borders on the Early Triassic Semeytau volcanic-plutonic structure. Mineralization is superposed on the Late Paleozoic complex of metadolerite and quartz porphyry dikes. Ore deposition was a long-term process comprising four stages. The first stage was related to deposition of slightly auriferous pyrite syngenetic to host rocks. The second stage is characterized by formation of the first productive (with invisible gold) fine-acicular arsenopyrite mineralization accompanied by sericitization and localized in the tectonic zone. The stockwork ore with pocket-disseminated base-metal mineralization and free microscopic gold of the third stage is hosted in silicified rocks. The ore formation has been completed by quartz-stibnite veins superposed on all preceding types of mineralization. According to Ar/Ar dating of sericite, a chronological gap between the second and the third stages is estimated at 33 Ma. The deposit is an example of polygenetic and multistage mineralization.