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

有人认为，岩石的东部部分的康艾。蒙古Khentei带由泥盆系或可能是石炭系包括放射虫岩和石炭系浅海沉积岩的增生杂岩组成（Tomurtogoo, 2003），但我们发现石炭系地层主要是增生杂岩的一部分。此外，在康艾东部可识别出以下3个剪切带。Khentei带。(1)该构造带北部岩石剪切强烈，构造不对称，呈现由上至北的剪切作用。构造层理一般为次水平，由434 ~ 462 Ma的同构造深成岩切割。此外，在哈拉地体的剪切岩石中还发现了277 Ma的花岗岩碎屑。这些事实表明，该地区的岩石被剪切两次：(a)在前志留纪，(b)至少在早二叠世之后。(2)北段发育北东向剪切带，构造不对称，表现为右向剪切。(3)南段剪切岩向北东向陡倾，构造不对称，具有左旋剪切作用。这些剪切岩被314 ~ 278 Ma的同构造花岗质岩体侵入。该剪切带穿过剪切带(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).