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 are and subsequent formation of an extended more than 6000 km long - Kazakhstan-Baikal orogenic belt. (C) 2007, IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved.