用浅层人工地震方法探测唐山-河间-磁县地震构造带内的活动断裂  

STUDY ON TANGSHAN-HEJIAN-CIXIAN EARTHQUAKE FAULT ZONE BY SHALLOW SEISMIC EXPLORATION METHOD

作　　者：王继 高战武 刘芳晓 王万合 赵国存[3] 徐伟 WANG Ji;GAO Zhan-wu;LIU Fang-xiao;WANG Wan-he;ZHAO Guo-cun;XU Wei(China Earthquake Disaster Prevention Center,Beijing 100029,China;CCTEG Xi'an Research Institute,Xi'an 710000,China;Institute of Crustal Dynamics,China Earthquake Administration,Beijing 100085,China)

机构地区：[1]中国地震灾害防御中心,北京100029 [2]中煤科工集团西安研究院有限公司,西安710000 [3]中国地震局地壳应力研究所,北京100085

出　　处：《地震地质》2020年第4期866-880,共15页Seismology and Geology

基　　金：国家重点研发计划项目(2017YFC1500401)资助。

摘　　要：由于唐山-河间-磁县地震构造带的位置、断错层位与上断的埋深尚不明确,在大名断裂、沧西断裂、大城东断裂附近布设了4条浅层地震勘探测线。测线DZ1位于邯郸市大名县东南部的龙王庙镇,以探测大名断裂。在该测线上共探测出5个断点,均为正断裂,上断点埋深95~125m,断距为6~12m,错断晚更新统而未错断全新统。DZ2测线位于沧州市献县县城东部,以探测沧西断裂。在该测线上共探测出3个断点,均为正断裂,上断点埋深170~190m,断距为7~10m,断裂上断点切割中更新统。DZ3和DZ4测线位于大城县里坦镇西,共探测出4个断点,上断点埋深120~130m,断距为5~15m,均为正断裂,断裂上断点切割中更新统。根据探测结果分析认为:大名断裂是晚更新世活动断裂,沧西断裂和大城东断裂是中更新世活动断裂,这3条断裂均有发生6级左右地震的能力。大城东断裂是先存地壳"深断裂"向上撕裂状扩展的"新生断裂"。The location of the buried faults,the fault broken layers and the depth of breakpoints in the Tangshan-Hejian-Cixian seismotectonic zone are not clear.We implemented 4 shallow seismic exploration profiles on the Daming Fault,Cangxi Fault,and Dachengdong Fault.Line DZ1 is located on the Daming Fault in the southeast of Daming County.Five breakpoints were dectectd,which are all normal faults,with depths of 95~125m and displacements about 6~12m,offsetting late Pleistocene but not the Holocene.Line DZ2 is located in the east of Xianxian County to dectect the Cangxi Fault.Three breakpoints were detected,all are normal faults,with depths of 170~190m and displacements about 7~10m.The upper breakpoints of the three faults cut the middle Pleistocene.The lines DZ3 and DZ4 are located in the west of Litan Town,Dacheng County.Four breakpoints were detected,with the upper breakpoint depth of 120~130m and displacements about 5~15m.They are all normal faults,and the upper breakpoints of the faults cut the Pleistocene strata.The result of the exploration of Cixian-Daming Fault is not consistent with the buried depth 1200m proposed by XU Hua-ming.It is proved that the activity of the fault is also consistent with the overall activity of the Cixian-Daming Fault,which is an active fault since late Pleistocene.The Dachengdong Fault and Cangxi Fault offset the middle Pleistocene strata.Although the late Pleistocene active faults are generally defined as active faults in the practice of active tectonics research in China,strong earthquakes in eastern China have shorter recurrence period,and earthquakes of magnitude 6 or so may also occur in some middle Pleistocene active faults.During the compilation of GB18306-2015“Seismic ground motion parameter zonation map of China”,there were no late Pleistocene active faults in the M6~6.5 potential source areas in eastern China.Therefore,we believe that the Dachengdong and Cangxi faults still have the ability to generate earthquake of magnitude 6 or so,and the faults have some similarities w

关 键 词：浅层地震勘探 唐山-河间-磁县地震构造带 隐伏断裂 

分 类 号：P31.2[天文地球—固体地球物理学]