渭河断裂带的构造演化与地震活动

TECTONIC EVOLUTION AND SEISMICITY OF WEIHE FAULT ZONE

渭河断裂带在前新生代为一条分割基底的古超壳断裂,新生代转为铲式伸展断裂,其伸展拉伸掀斜作用形成了渭河盆地的雏形,现代以引张倾滑兼枢纽运动为特征。该断裂带为渭河盆地一条最显著的地震活动带,自公元前280年以来有20次5级以上地震与该断裂带有关。

Transversing the axis of Weihe basin,the Weihe fault zone varied in nature in different geologic period: before the Cenozic it was a transcrustal paloefault zone cutting the basement,during the Cenozoic it changed into a listric extensional fault and formed the embryozic Weihe basin by extension and tilting and recently it has been Characteristic of an extension and dip slip along with hingelike movement.The fault is a famous seismic zone along which there have been 20 earthquakes with since 280a B.C.