太行山东麓断裂带中、新生代构造应力场及转换机制  

Meso-Cenozoic Stress Fields and Their Transition Mechanisms in the Eastern Taihang Mountain Fault Zone

作　　者：安慧婷[1] 许立青[1] 李三忠[1] 余珊[1] 刘鑫[1] 索艳慧[1] 曹现志[1] 赵淑娟[1] 王鹏程[1] 郭玲莉[1] 戴黎明[1] 

机构地区：[1]中国海洋大学海洋地球科学学院,海底科学与探测技术教育部重点实验室,山东青岛266100

出　　处：《大地构造与成矿学》2015年第4期571-586,共16页Geotectonica et Metallogenia

基　　金：中国地质调查局项目(12120113105200);863重点项目(2009AA093401);重大项目课题(41190072和41325009)联合资助

摘　　要：太行山东麓NNE向断裂带,主要由太行山大断裂和太行山山前断裂组成,统称为太行山东麓断裂带。通过节理统计和野外构造观测,对太行山东麓断裂带进行了构造应力场分析,探讨其中、新生代构造应力场差异和应力场的转换机制。研究结果表明,该区自中生代以来发生了5期局部应力场的变化,其最大主压应力轴方位分别为NW向、NE向、NWW向、近SN向(NNE或NNW向)和NEE向。这5期应力场分别对应中侏罗世-早白垩世的燕山期NW-SE向挤压、古新世-始新世NE-SW向挤压、始新世-渐新世NWW向挤压、中新世-早更新世近SN向挤压以及中更新世以来NEE向挤压。区域对比表明,总体上为两大动力系统引发的应力场交替,转换机制可能为:早期挤压受太平洋板块向西俯冲到东亚安第斯型大陆边缘导致华北克拉通破坏的影响;中期受太平洋板块俯冲方向转变制约;晚期伸展则与印度和欧亚板块碰撞激发的软流圈向东的扩张效应和太平洋俯冲带跃迁式东撤的联合效应–区域性"东进西退"深部机制有关。Two important subparallel faults, namely the Large Taihang Mountain Fault and the Eastern Taihang Mountain Fault, are major faults developed in the Taihang Mountain region. To revel the differences and the transition mechanisms of Meso-Cenozoic stress fields, we studied the stress fields along the Eastern Taihang Mountain Fault Zone through combined statistics and field-based structural observations. Our results show that there are five stages of local stress fields in the area since ever Mesozoic. The directions of maximum principal stresses of the five stages are NW-directed, NE-directed, NWW-directed, NNE-NNW （near-SN）-directed, and NEE-directed, respectively. The five-stage stress fields correspond to NW-SE-directed compression in the Jurassic-Early Cretaceous-Yanshanian, NE-SW-directed compression in the Paleocene-Eocene, NWW-SEE-directed compression in the Eocene-Oligocene, near S-N-directed compression in the Pliocene-early Pleistocene, and NEE-directed compression since the middle Pleistocene, respectively. The regional dynamic correlations show that the early-stage compression may have resulted from the destruction of the North China Craton that caused by the westward subduction of the Pacific Plate to the East Asian Andean-type continental margin, and the middle-stage extension is possibly related to a direction change of subduction of the Pacific Plate, whereas the late-stage extension may have resulted from the eastward upwelling of the asthenosphere that caused by the collision of the Indian to the Eurasian plates and the eastward rollback of the Pacific subduction zone.

关 键 词：太行山大断裂 太行山山前断裂 节理分析 中 新生代 应力场 转换机制 

分 类 号：P542[天文地球—构造地质学]