贝加尔裂谷带中部的新构造特征及其成因分析

位于贝加尔裂谷带中部的滨奥里洪地区主要包括3个大地构造单元:西部滨海山脉、滨奥里洪高原和小海地堑.笔者着重对该地区中新世以来的新构造活动特征,特别是对第四纪夷平面的变化、断层的发育、河流的变迁、河流阶地的发育等进行了研究,表明该地区在中新世以来具有强烈的拉张运动与升降运动特征,是贝加尔裂谷带新构造运动表现最强烈的地区.新生代贝加尔裂谷带的发育受印度板块-欧亚板块碰撞、西太平洋俯冲引起弧后扩张作用的影响;中部滨奥里洪地区受到NW-SE向拉张作用,发育了强烈的新构造.

Neotectonic features and its formation mechanism in the central part of Baikal Rift Zone,Russia

The Olchon Region,which is located in the central part of Baikal Rift Zone,includes threemain tectonic units:Primorsky ridge,Maloye More Basin and Olchon Plateau from west to east.Thispaper describes the features of geotectonic activities in the Olchon Region since Miocene,such aschange of Quaternary plantation surface,developments of faults,evolution of the rivers,and forma-tion of river terrance.The study result shows that the Olchon Region has experienced both strong ex-tension and vertical motion since Miocene.The development of Baikal Rift Zone in Cenozoic wascontrolled by both the India-Eurasia collision and back-arc spreading caused by Pacific Plate's sub-duction to Eurasian Plate.The Olchon Region experienced strong NW-SE extension and intensivegeotectonic movement.