内蒙古大青山山前断裂带构造变形特征

大青山山前断裂带沿大青山山前呈近东西方向展布，是河套新生代断陷盆地形成的主要控制断裂，由一系向南倾斜的阶梯状高角度断层组成。断裂带活动以北升南降的垂直差异运动为主，具有长期活动发展演化历史。该断裂带在白垩纪时期开始形成，其活动可划分为5 个演化阶段: 早白垩世初始形成阶段、古近纪-新近纪、早中更新世、晚更新世和全新世构造变形阶段。该断裂带的形成受区域构造应力场控制，是区域上南北向伸展而形成的近东西方向张性正断层。

Structural deformation characteristics of Daqingshan piedmont fault in Inner Mongolia

Daqingshan piedmont faults consist of a number of stepladder high angle southward faults,extended in the Daqingshan piedmont in east-west direction,and controlling the formation of Hetao faulted basin.The fault activity is charactered by vertical differential movement with north up and south down.There is long history of formation and development of the Daqingshan piedmont faults.The faults originate in Early Cretaceous,and their evolution can be divided into five stages: the Early Cretaceous original development stage,Paleogene-Neogene,early-middle Pleistocene,late Pleistocene,and Holocene structural deformation stages.The development of Daqingshan piedmont faults were controlled by regional tectonic stress field,and extended in south-north direction to form the tensional normal faults with east-west direction.