Вестник МГТУ. 2018, том 21, № 1.

Вестник МГТУ. 2018. Т. 21, № 1. С. 61–79. DOI: 10.21443/1560-9278-2018-21-1-61-79 65 while the water content in the diagenized varieties drops to 10–15 %. Such hydromicas as illite, smektite, montmorillonite, kaolin, and diaspora form in argillaceous rocks with a large amount of organic matter (0.5 to 1.0 %). Fig. 4. Abiotic-genesis hydrocarbon generation mechanisms in convergent and divergent settings: 1: mantle asthenosphere; 2: oceanic-type crust; 3: oceanic lithosphere; 4: island-arc-type structural and compositional units; 5: caldera-type volcano-sedimentary units; 6: deep-seated hearths of carbonatite and kimberlite magma melting; 7: granitoid intrusions; 8, 9: sedimentary units: 8: poorly defined units of oceanic and island-arc-type sediments; 9: oceanic sediments; 10: area of maximum manifestation of stress metamorphism; 11: generalized tectonic dislocations; 12: area of partial subducting lithospheric plate disintegration; 13: trend of convective currents in the mantle; 14: encapsulated solid and gas-liquid inclusions of disintegrated crustal rocks; 15: hydrothermal structures at the sea bottom; 16: trend of chemical compound degassing; 17: ocean level Рис. 4. Механизмы генерации углеводородов абиогенного происхождения в конвергентных и дивергентных обстановках: 1 – астеносфера мантии; 2 – кора океанического типа; 3 – океаническая литосфера; 4 – структурно- вещественные комплексы островодужного типа; 5 – осадочно-вулканогенные комплексы кольдерного типа; 6 – глубинные очаги плавления карбонатитовых и кимберлитовых магм; 7 – гранитоидные интрузии; 8, 9 – осадочные комплексы: 8 – нерасчлененные комплексы осадков океанического и островодужного типов; 9 – океанические осадки; 10 – зона максимального проявления стресс-метаморфизма; 11 – генерализованные тектонические нарушения; 12 – зона частичной дезинтеграции субдуцирующей литосферной плиты; 13 – направление конвективных течений в мантии; 14 – закапсулированные твердые и газово-жидкие включения дезинтегрированных пород корового состава; 15 – гидротермальные постройки на морском дне; 16 – направление дегазации химических соединений; 17 – уровень океана At an early stage of metamorphic transformations sediments and sedimentary rocks drawn in the subduction zone undergo intense dehydration. Firstly, they lose porous (free), and then crystallization water with subsequent development of a complex series of endothermic (heat-absorption-related) metamorphic transformations accompanied by the release of water, CO 2 , silica, alkalis (especially potassium), and lithophile elements. In the maximum compression zones, the rocks become consolidated and partially seal generated solutions creating high fluid pressure and expanding the water-bearing minerals stability field. The majority of such fluid flows move from the bottom up and laterally, or perpendicular to the long axis of folding from the area of high pressure to the zones of tectonic shadow. In case of existing tangential pressure gradient in the permeable medium, the movement of these flows and their transition from one metamorphic facies to another shall always be observed (Fig. 5). The given sketch successfully reflects the specific nature of metamorphic facies field correlation, where the separating zones represent the transition areas from one facies to another. Exactly in these areas at the borders of stability fields, processes of mineral phase recrystallization begin and rigorously proceed. Analyzing the sketch, it is possible to come to another very important geodynamic conclusion. At larger depths, in the subduction zones, the contact edge for the lithospheric plates fades away, mineral assemblages stay under the physical and chemical equilibrium state, and fluid phase acquires features of a supercritical liquid. This effect above all, arises due to the affinity of chemical composition for the substance of the third oceanic and undercrust continental lithosphere layer. As a result, the degrading