MAIN SERIES OF ZONING OF HYDROTHERMAL MINERAL DEPOSITS

Abstract

The main series of hydrothermal deposits zoning are considered in the article. These include stable series of zoning of ore elements, which reflect (1) successive alternation of maxima of concentration of elements in a certain direction, (2) spatial orientation of series of zoning, (3) sequence of development of series of zoning over time (or its directionality). The series of zoning can be composed by elements, minerals, paragenesises, quantitative ratios of the main elements, trace elements, metasomatites, physicochemical conditions of formation, etc. It is also necessary to study the elements of symmetry of zoning: the symmetry of veins, faults, dykes, contacts of intrusive massifs, lithologically favourable zones, axial lines (diatremes), as well as to determine the vectors (trends) of changes in mineralization (concordant, intersecting, intermediate (contact). According to the orientation of the vector in relation to the elements of symmetry, deposits with bilateral zoning (divergence and convergence) and central zoning (centripetal and centrifugal) are distinguished. The sequence (direction) of the development of zoning series over time is inherent only to polyascendant zoning and is essentially progressive and regressive. Geochemical series of zoning made it possible to divide all deposits into seven groups and 22 subgroups: 1) group of siderophile elements (contains two subgroups); 2) sidero-chalcophile (three); 3) chalcophile (four); 4) litho-chalcophile (five); 5) lithophilic (five); 6) sidero-lithophilic (one); 7) group of litho-sidero-chalcophile elements (contains two subgroups). As a result, three “summarizing” zoning series (А, Б, В) with a common change of zoning series were selected. The zoning of mineralization of hydrothermal deposits makes it possible to solve the problem of the erosional section, distinguish, forecast, develop and improve the geological and genetic classification of deposits, and improve the rational system of prospecting for deposits.