PROSPECTS OF ORE-BEARING CARBONACEOUS DEPOSITS OF AMUR STRATIFORM FIELD ON THE ZINC MINERALIZATION (SOUTHERN URALS)

摘要

The paper considers the geological structure of the Amur stratiform zinc deposits in the geological section of which distinguished three strata: molassic, terrigenous-carbonate (flyschoid) and volcanogenic. Describes the parameters of the ore body, its composition, the types of ores and the content of useful components, forms of their presence, reflected the different views of researchers on the history of the formation of the deposit. Special attention in the paper is paid to carbonaceous deposits, which are widely represented in flyschoid stratum. It is shown that black shales belong to low carbon type, as well as terrigenous-carbonaceous and carbonate-carbonaceous formations. Paleogeographic conditions of their deposition corresponded to a shallow basin, within which there where a local depressions. In these local depressions occured the accumulation of pyrite-sphalerite mineralization coming through the narrow channels from the north-west direction (from the Magnitogorsk megazone) with intense volcanism and activities of “black smokers”. In one of these depressions formed the Amur deposit, and the other, situated farther north-east from it – zinc ores the most perspective area within the geological allotment. In the deeper basin depression (located farther south of the deposit) with a higher concentration in the near bottom of the hydrogen sulfide, in the absence of connection with the areas of volcanism, was formed the sediments with pyrite-pyrrhotite mineralization. The north-eastern section was drilled with a series of core holes to test the prospect for zinc ores. Five of the eight exploratory wells have uncovered the ore body with thickness from 6 to 16 meters, which allowed to calculate here inferred resources of zinc by P1 category in the amount of 400 thousand tons.