中国东部及邻区中新生代构造演化与太平洋板块运动

中新生代以来,我国东部及邻区濒临太平洋区域广泛发育着一个规模宏伟、活动强烈的北东—北北东向构造体系。对此构造体系的性质及其动力来源有着几种不同的看法。本文根据地质构造和地球物理资料分析了本区构造形变和构造应力场特征,认为,北东—北北东向构造的不同性质是不同发展阶段的产物。我国东部构造形变和构造应力场自中生代以来经历了三个重要的演化阶段,各阶段的构造动力与太平洋内各时期板块运动的方向和边界条件有着密切关系。

MESO-CENOZOIC TECTONIC EVOLUTION OF EASTERN CHINA AND ADJACENT AREA AND MOVEMENT OF THE PACIFIC PLATE

The tectonic system trending in NE-NNE direction in eastern China has gone through three distinct stages of development,among which the early one was compression with left lateral shear the middle was extentional and the late one was compression with right lateral shear.Their developmental processes are compatible with three changes of tectonics of the Pacific plate since Mesozoic.According to the directions of movement,boundary conditions and the characteristics of subduction zone during’changes of Pacific plate,the relation between the tectonic evolution of eastern China and the movement of Pacific plate is stressed in this paper The authors consider the motion of Pacific plate as the main cause of tectonic alterations in eastern China and adjacent area since Mesozoic.Finally based on the migration mode of upper mantle materials from the subduction zong deep in mantle,the dynamic model of tectonic alteration in eastern China is discussed.