Was there the "Mongol-Okhotsk Ocean?"-On tectonic evolution of Eurasian Continent-

据认为，康盖山东部的岩石。蒙古庆泰带由泥盆纪或石炭纪增生杂岩组成，包括放射虫硅质岩和石炭纪浅海沉积岩(Tomurtogoo，2003)，但我们揭示石炭纪建造主要是增生杂岩的一部分。此外，在汉盖东部还发现了以下三条剪切带。(1)该带北段岩石强烈剪切，构造不对称，具有自顶向北的剪切感。构造面理一般为近水平面理，由434~462 Ma的同构造深成岩切割而成。此外，在哈拉地体的剪切岩石中还包括277 Ma的花岗岩碎屑。这些事实表明，该区岩石经历了两次剪切作用：(A)在前志留纪，(B)至少在早二叠世之后。(2)北东向剪切带发育，其构造呈右旋剪切。(3)南段北东向陡倾的剪切带岩石具有不对称构造，表现为左旋剪切带。这些剪切岩石是由314~278 Ma的同构造花岗岩侵入的。该剪切带横切剪切带(2)，并受到剪切带(1b)的干扰。

It have been considered that the rocks of the eastern part of the Khangai. Khentei belt, Mongolia were composed of Devonian or possibly Carboniferous accretionary complexes including radiolarian chert and Carboniferous shallow marine sedimentary rocks(Tomurtogoo, 2003), but we revealed that the Carboniferous formation is mostly a part of the accretionary complexes. In addition, the following three shear zones are recognized in the eastern part of the Khangai. Khentei belt.(1) The rocks of the northern part of this belt are intensely sheared with asymmetric structures showing a top-to the North sense of shear. The tectonic foliation is generally sub-horizontal and is cut by syn-tectonic plutonic rock dated between 434 and 462 Ma. Added to this, a granitic clast of 277 Ma is included in a sheared rock of the Haraa terrane. These facts suggest that the rocks of the area were sheared twice :(a) at pre-Silurian, and(b) at least after Early Permian.(2) A shear zone trending NE with asymmetric structures showing a dextral sense of shear is developed in the northern part of the belt.(3) The sheared rocks of the southern part of the belt which trend NE with steep dipping have asymmetric structures indicating a sinistral sense of shear. These sheared rocks are intruded by syn-tectonic granitic rocks dated between 314 and 278 Ma. This shear zone cuts across the shear zone(2) and is disturbed by the shear zone(1b).