ГЛУБИННАЯ ГЕОДИНАМИКА И ОСОБЕННОСТИ МЕТАЛЛОГЕНИИ КУНАШИР-УРУПСКОГО ЗВЕНА КУРИЛЬСКОЙ ОСТРОВОДУЖНОЙ СИСТЕМЫ

Abstract

The southern part of the Kuril island-arc system (from Kunashir to Urup islands) differs from the northern part (from Simushir to Paramushir islands) in its spatial arrangement relative to the subducting Pacific megaplate’s motion vector, greater number of volcanoes, and endogenic mineralization diversity (Au, Ag, PGE, Re, IN, Sn, Cu, Zn, Pb and others). The location of deep northwest-trending zones of strike-slip faulting on the opposite oceanic slope of the Kuril Trench is another peculiarity of the Southern Kurils. Significant extent (up to 1000 km), great depth (more than 100 km) and permanent (J-Q) activity of the strike-slip faults allowed thermal-fluid flows from the undersubduction asthenosphere to penetrate through the seismic focal zone, above the mantle wedge and oversubduction asthenosphere and reach subcontinental lithosphere. The upwelling of the flows was accompanied by metasomatic processes, formation of initial magma reservoirs and both the transitional and peripheral reservoirs in the Kuril island-arc crust, as well as by the evolution of volcanic activity and ore genesis. The synthesis of the Southern Kurils’ metallogeny and geodynamics data allows us to recognize the islands as a natural phenomenon intended for study of geological problems and mineral resources exploitation.