PRISHILKINSKY MINERAGENOUS AREA: REAL-TIME CRITERIA OF ORE CONTENT
Prishilkinsky mineragenous area is located on the N-sheets 50, 51 and M-49, 50, extending in northeastern direction through the territory of East Transbaikalie and the Upper Amur region for 850... 900 km. The fragments of this unique mineragenous unit were allocated previously by many geologists, but it has been fully defined at the beginning of this century as a result of making the State Geological Maps of the Russian Federation with the scale 1: 1,000,000 of the third generation. Scientific and practical interest to this major structural-material formation is associated with regional structural features favorable for the formation of large deposits and the Transsiberian railway, running along or near this zone numerous polymineral objects, including large deposits of scarce minerals. However, the established database of geological information, designed to meet the economic conditions of Russia still needs refinement, improvement of some geological positions in the effectiveness of forecasting research, as well as the choice of the priority areas of prospecting and exploration projects.Seven articles published in 2014-2015 in the Journal of Transbaikal State University, are dedicated to the main features of Prishilkinsky structural formational complex formation and the same corresponding mineragenous area. In the next article of this series, the features of geological formations (formations, rocks) that allow you to identify direct signs of malicious ores and indirect - geological background are described. The questions of metamorphic and metasomatic rocks, formation-genetic series metasomatism and mineralization, geochemical specialization of structure-formation of complexes, as well as the era of ore genesis are observed. The processes of mineral formation ultra-metamorphism of regional progressive, regressive, dislocation and contact metamorphism and metasomatism associated with the formation of Precambrian granitoids and Phanerozoic are summarized. 14 species of hydrohermal-metasomatic rocks and 20 hydrothermal metasomatic formations associated with granitoid, ultrabasic - basic and ultrabasic - alkaline rocks are presented. On the basis of litho-Khalq-siderophilic method 25 groups of associations of chemical elements are allocated; geochemical specialization of rocks is often transformed into mineragenetic ones. The promising geochemical associations 8 geological complexes and suites are allocated from them. It was found that the main feature of lithophilic-chalcophilic and chalcophilic groups and associations is the constant presence of elevated gold content. The formation of the main mass of commercial deposits of various genetic, geological and industrial types is associated with Late (Cimmerian) era of the Middle Jurassic period - Early Cretaceous