Caucasus region is located in the center of Alpine-Himalayan orogenic belt. It is made of two Great and Lesser Caucasus fold thrust belts and an intramountain area called Trans caucasus or Mid caucasus. This region co...Caucasus region is located in the center of Alpine-Himalayan orogenic belt. It is made of two Great and Lesser Caucasus fold thrust belts and an intramountain area called Trans caucasus or Mid caucasus. This region contains a system of oceanic crust subduction, island arcs, volcanic arcs, back arc basins and rifts. The earthquakes of 60 km in depth are the evidences of deep brittle zone under Great Caucasus. Without considering Prototethys, Paleotethys and Neotethys Oceans, the tectonic situation of this region is not possible to study. The oceanic lithosphere under oceanic lithosphere subduction made Trans caucasus containing a trans crust. The subduction of Prototethys under Baltic made Great Caucasus and the subduction of Paleotethys under Iran, made Lesser Caucasus. The earth sutures caused by the closure of Prototethys and Paleotethys Oceans are clear in the region. The direction of Paleotethys subduction in lesser Caucasus is a considerable issue. Most of the existing evidences prove the southward direction which is different from Paleotethys subduction in Alborz of Iran. The lithospheric type of Midcaucasus is different from Caspian. Midcaucasus plays the role of determining collision type in the region.展开更多
文摘Caucasus region is located in the center of Alpine-Himalayan orogenic belt. It is made of two Great and Lesser Caucasus fold thrust belts and an intramountain area called Trans caucasus or Mid caucasus. This region contains a system of oceanic crust subduction, island arcs, volcanic arcs, back arc basins and rifts. The earthquakes of 60 km in depth are the evidences of deep brittle zone under Great Caucasus. Without considering Prototethys, Paleotethys and Neotethys Oceans, the tectonic situation of this region is not possible to study. The oceanic lithosphere under oceanic lithosphere subduction made Trans caucasus containing a trans crust. The subduction of Prototethys under Baltic made Great Caucasus and the subduction of Paleotethys under Iran, made Lesser Caucasus. The earth sutures caused by the closure of Prototethys and Paleotethys Oceans are clear in the region. The direction of Paleotethys subduction in lesser Caucasus is a considerable issue. Most of the existing evidences prove the southward direction which is different from Paleotethys subduction in Alborz of Iran. The lithospheric type of Midcaucasus is different from Caspian. Midcaucasus plays the role of determining collision type in the region.
