西秦岭北缘断裂带活动构造地貌特征及其形成机理  

Morphologic Characteristics and Formation Mechanism of the Active Tectonics Along the North Fringe Fault Zone of West Qinling Mountain

作　　者：康来迅[1] 

机构地区：[1]国家地震局兰州地震研究所

出　　处：《华东师范大学学报（自然科学版）》1994年第2期67-75,共9页Journal of East China Normal University(Natural Science)

摘　　要：本文根据大量的野外调查资料和Ｃ１４年代数据，并结合青藏高原东北部地壳厚度、震源深度和震源机制等资料的分析，讨论了本断裂带活动构造地貌的分布特点、期次及其形成机理等问题。本文认为一系列山脊、阶地、水系和洪积扇沿西秦岭北缘断裂带反扭错位变形，变形强度由西向东逐渐增大，并且可以划分为３期变形。这种反扭错位变形，是西秦岭北缘断裂带南、北两侧地壳浅部块体向东运动过程中，因北侧块体速度较慢产生的滞后效应现象。On the basis of abundant information from field investigation and C14 dating,and combining with analysis of the crust thickness.focal depth,focal mechanism in the northeast of Qinghai──Xizang Plateau,the distribution characters,the stage division and the forming mechanism of the active tectonic landform along the north fringe fault zone of West Qingling Mountain are discussed.The paper thinks that the reverse torsional dislocations of mountain ridgs,terraces,drainage systems and pluvial fanes along the faul zone of north fringe of West Qingling Mountain,enlarging from the west to the east,can be divided into three sequences.The reverse torsional dislocations,in fact,come from the hysteresis effects that result from lower velocity of its north side during the movement of the shallow crust masses toward the east on both sides of the fault zone of north fring of WestQinglng Mountain.

关 键 词：活动构造地貌 断裂带 地震 

分 类 号：P315.2[天文地球—地震学]