Publishing House SB RAS:

Publishing House SB RAS:

Address of the Publishing House SB RAS:
Morskoy pr. 2, 630090 Novosibirsk, Russia



Advanced Search

Russian Geology and Geophysics

2001 year, number 8

Late Vendian age of the Khan-Taishiri ophiolite complex in western Mongolia

Gibsher A. S., Khain E. V., Kotov A. B., Sal'nikova E. B., Kozakov I. K., Kovach V. P., Yakovleva S. Z., and Fedoseenko A. M.
Keywords: Late Vendian, U-Pb method, ophiolites, continental margin, island-arc system, Khan-Taishiri Ridge, western Mongolia, Central Asia
Pages: 1179-1185

Abstract

The age of ophiolite plagiogranites from the Khan-Taishiri ophiolite complex, western Mongolia, was determined by the U-Pb zircon method as 568.1 4.0 Ma. This complex is a rare fragment of the ancient Central Asian blocks where real geological relationships within large tectonic slabs making up the ridge have been established between all ophiolite sequences but ultrabasic rocks: pyroxenite and gabbro from banded sequence, basic rocks of dike complex, dolerite sills, basic pillow lava, and deep-water clay-siliceous sediments.
The Neoproterozoic age of the Khan-Taishiri ophiolite complex suggests the presence of a Vendian island-arc system within the Central Asian Mobile Belt. The model for this system was described for the first time by L. P. Zonenshain and O. Tomurtogoo on geologic objects of western Mongolia from Dzavhan River to northern slopes of the Mongolian Altai Ridge (Dzavhan, Gobi-ALtai, Khan-Taishiri, Naran, Ulan-Shandian, and Kuroi subzones). This system obviously included the Daribi ophiolites of western Mongolia; the Agardag and Shishkhid ophiolites of Tuva; the Dzhida and Ol'khon fragments of island-arc system; the belt of subductional layered massifs of Northern Baikal and eastern frame of the Muya Block; the Naran, Eastern Sangilen, Southern Khamar-Daban, OL'lhon, and Bodaibo fragments of sedimentary basin; the Dzavhan, Hovsgol-Bokson, Western Baikal, and Baikal-Patom shelf fragments. Ocean lithosphere was represented by Bayan-Khongor ophiolites.