摘要
根据对渭河盆地地貌、水系格局的分析,本文提出:(1)渭河盆地地区新构造运动主要表现为以近东西向、北西向和北东向几组断裂控制下的断块运动;(2)断块运动自南而北呈波浪式发展,且具多期活动的特点,可分为老第三纪、中新世、上新世—更新世初、更新世末—全新等世四个活动期;(3)新构造运动具有明显南强北弱、东强西弱的差异性,华阴—华县一带最强,为应力集中区;(4)盆地新构造应力场的主压应力方向为48°～79°。
Based on an analysis of landforms and the drainage system in the Weihe Basin, the characteristics and the stress field of the neotectonic movement are discussed in this paper.The main conclusions are as follows:
1 In the Weihe Basin, the neotectonic activity is mainly characterized by the fault-block movements, which are gradually developing wave upon wave from the south to the north.
2 Since the Eogene period, this fault-block movement has experienced four moving episodes: Eocene, Miocene, Pliocene the early Pleistocene and the late Pleistocene-Holocene.
3 The neotectonic activities appear distinct differences in the regions of the Weihe Basin, where the south is more active than the north, and the east more active than the west.In the Huayin-Huaxian areas to the southeast of the basin they are the strongest, forming a stress concentrated segment.
4 The orientation of the maximum principal stress in the neotectonic stress field of the basin is 48°~79°.
关键词
渭河
盆地
地貌
水系格局
构造活动
Fault-block movement, Wavy movement, Polyphase activity, Neotectonic stress field, The pattern of river systems
