摘要
Based on the analysis of known geodynamic models that explain the processes in various geodynamic settings of the Meso-Cenozoic stages of the development of continental margins and the tectonic-magmatic events accompanying these processes, as well as on the basis of our own data obtained as a result of many years of research on the axial structure of the Central Asian Fold Belt-Mongol-Okhotsk orogenic belt and the influence of interdependent structures on the post-Mesozoic evolution of the eastern flank of the Mongol-Okhotsk orogenic belt was substantiated by us. The closure of the Mongol-Okhotsk basin due to the approach of the Siberian and North China cratons was accompanied by a change in geodynamic conditions: subduction, collision, intraplate-rift and was reflected in the formation of synchronous igneous complexes in the frame of the Mongol-Okhotsk orogenic belt. In the northern frame of the belt, the distribution of magmatites is cut off by the structure of the Selenga-Stanovoy superterrane in the west. The northern boundary of the superterrane is the zone of the Dzheltulak fault. In the south, it borders on the Mongol-Okhotsk orogenic belt along the zone of tectonic melange. We believe that evolutionary processes within the orogenic belt and its framing continued into the post-Mesozoic time after the final formation of the belt as an orogen. The position of the Selenga-Stanovoy superterrane in the late Mesozoic did not correspond to the modern one. The structures of the Central Asian fold belt located between the Mongol-Okhotsk orogenic belt and the Siberian craton in the Cenozoic were influenced by collisional processes occurring between the Indian and Eurasian plates. And these processes were not only the “driving force” for the movement of the Selenga-Stanovoy superterrane in the post-Mesozoic time, but also changed the structure of the Mongol-Okhotsk orogen, dividing it into two flanks.
Based on the analysis of known geodynamic models that explain the processes in various geodynamic settings of the Meso-Cenozoic stages of the development of continental margins and the tectonic-magmatic events accompanying these processes, as well as on the basis of our own data obtained as a result of many years of research on the axial structure of the Central Asian Fold Belt-Mongol-Okhotsk orogenic belt and the influence of interdependent structures on the post-Mesozoic evolution of the eastern flank of the Mongol-Okhotsk orogenic belt was substantiated by us. The closure of the Mongol-Okhotsk basin due to the approach of the Siberian and North China cratons was accompanied by a change in geodynamic conditions: subduction, collision, intraplate-rift and was reflected in the formation of synchronous igneous complexes in the frame of the Mongol-Okhotsk orogenic belt. In the northern frame of the belt, the distribution of magmatites is cut off by the structure of the Selenga-Stanovoy superterrane in the west. The northern boundary of the superterrane is the zone of the Dzheltulak fault. In the south, it borders on the Mongol-Okhotsk orogenic belt along the zone of tectonic melange. We believe that evolutionary processes within the orogenic belt and its framing continued into the post-Mesozoic time after the final formation of the belt as an orogen. The position of the Selenga-Stanovoy superterrane in the late Mesozoic did not correspond to the modern one. The structures of the Central Asian fold belt located between the Mongol-Okhotsk orogenic belt and the Siberian craton in the Cenozoic were influenced by collisional processes occurring between the Indian and Eurasian plates. And these processes were not only the “driving force” for the movement of the Selenga-Stanovoy superterrane in the post-Mesozoic time, but also changed the structure of the Mongol-Okhotsk orogen, dividing it into two flanks.
作者
Inna Derbeko
Inna Derbeko(Institute of Geology and Nature Management, Far Eastern Branch Russian Academy of Sciences, Blagoveschensk, Russia)
