Выпуск 48
Автор(ы):Buslov M.M., Dobretsov N.L.
Издание:Russian Geology and Geophysics, 2007 г., 12 стр.
Late Cambrian-Ordovician tectonics and geodynamics of Central Asia

In the Late Cambrian-Ordovician, Gondwana-derived microcontinents such as Kokchetav, Altai-Mongolian, Tuva-Mongolian, and Barguzin, as well as the Kazakhstan-Tuva-Mongolian island arc or a system of island arcs were involved in intense accretion-collision processes in similar geodynamic settings on a vast territory of Central Asia — from West Kazakhstan to Lake Baikal. The processes were likely to be the result of a large rebuilding of the Earth’s crust possibly related to the increased mantle impact on the lithosphere as they were simultaneous to the opening of the Uralian and Mongolian-Okhotsk (Turkestan) Oceans. The 970–850 Ma breakup of Rodinia and the 760–700 Ma important tectonic events were followed by the Late Cambrian-Early Ordovician plume magmatism impulse at 500–480 Ma, which led to the opening of new oceans and accelerated the accretion of the Gondwana-derived blocks to the island arc and subsequent formation of an extended — more than 6000 km long — Kazakhstan-Baikal orogenic belt.

ТематикаРегиональная геология
Том 17, Выпуск 3
Автор(ы):Bogdanova S.V., Li Z.X., Pisarevsky S.A.
Издание:Stratigraphy and Geological Correlation, 2009 г., 16 стр.
Assembly and Breakup of Rodinia (Some Results of IGCP Project 440)

The principal results of project 440 “Assembly and Breakup of Rodinia” of the International Geological Correlation Programme (IGCP) are reviewed in this work. A map of that supercontinent compiled using geological and paleomagnetic data describes global paleogeography 900 Ma ago. The assembly of Rodinia, which comprised most of Precambrian continental blocks, lasted ca. 400 m.y. (from 1300 to 900 Ma). Its breakup presumably triggered by mantle superplume took place between 830 and 650 Ma. The correlation between tectonic events in different continental blocks is considered. Some problems concerning the Rodinia reconstruction and history, e.g., the slow growth of juvenile crust and effects of mantle-plume events during the amalgamation period and of glaciations at the breakup time, are discussed. The latter caused changes in the biosphere and climate, whereas postglacial periods stimulated progress in biota evolution

ТематикаИсторическая геология
МеткиGlaciation, Mantle plume, Mesoproterozoic, Neoproterozoic, Paleogeographic reconstruction, Rodinia, Ssupercontinent, Глобальное оледенение, Мантийные плюмы, Палеогеографическая реконструкция, Родиния
Ленты новостей