太平沟断裂的新发现与1963年黑龙江萝北5.8级地震的关系研究  

The New Discovery of Taipinggou Fault and the Relationship with M 5.8 Earthquake in 1963 in Luobei County, Heilongjiang Province

作　　者：余中元[1,2] 闵伟[2] 韦庆海 刘玉刚[2] 高峰 

机构地区：[1]黑龙江省地震局,哈尔滨150090 [2]中国地震局活动构造与火山重点实验室中国地震局地质研究所,北京100029

出　　处：《震灾防御技术》2017年第1期31-39,共9页Technology for Earthquake Disaster Prevention

基　　金：中国地震局星火计划项目"依兰-伊通断裂黑龙江段新活动的几何展布图像研究"(XH14018Y);黑龙江省地震局科研项目"依舒断裂黑龙江段历史地震韩史记录的挖掘与考证"(201605);黑龙江省国土科技研究项目"依舒断裂第四纪构造活动研究";国家自然科学基金项目(41272235)联合资助

摘　　要：黑龙江省萝北地区是东北现代地震活动最为活跃的地区之一,中小地震密集成带分布,曾于1963年发生5.8级地震,但其发震构造一直不清楚。精定位后的震中分布图像和震源机制解研究结果表明,现代地震总体呈NEE方向密集分布于黑龙江小兴安岭山前太平沟一带,地震类型以右旋走滑为主。通过高分辨率的卫星影像解译结果发现太平沟一带发育一条长约25km,走向约N70oE的线性异常带。野外地表调查发现该线性异常表现为断续分布的断裂陡坎、冲沟位错和滑坡。陡坎走向约N65oE—N75oE,倾向SE,高约1.0—2.5m;滑坡发育有典型的弧形圈椅构造,规模大小不等,多与断裂陡坎伴生。综合现代地震活动图像、卫星影像解译、野外地质调查结果,特别是结合2013年11月和2014年2月该地区的2次小震活动及现代地震活动的空间图像分布特征,研究认为太平沟断裂属于依兰-伊通断裂带的分支断裂,晚第四纪期间曾经强烈活动,具备中强地震的发震能力,可能是萝北1963年5.8级地震的发震构造。Luobei County is one of the most active areas of modem seismic activity in northeast China in recent years. Medium and small earthquake distributed intensively zonal in this region, and was hit by a M5.8 earthquake on June 21, 1963, and the seismogenic structure of which is still in dispute. The relocated epicenter distribution map and focal mechanism solution show that these events mainly distributed in the Taipinggou area with a narrow NEE strike strip, and earthquake types is given priority to dextral strike-slip with small amounts of thrust component. Satellite imagery interpretation results indicate that there exists a - 25km linear anomaly belt with N70°E strike in the Taipinggou area of Xiaoxing＇anling Mountains piedmont. Further field geological investigation found that the belt consists of discontinues fault scarps, dislocated gullies and landslides. The heights of fault scarps vary from 1.0m to 2.5m. The fault scarps also show that the fault strikes N65°E-N75°E, dipping SE, with clear right-lateral slip movements implicated by the dislocated gullies. The Arc round-backed armchair structure developed companied with the scarps has different height ranging from several to dozens of meters. We suggest that the Taipinggou fault, as the associated structure of the Yilan-Yitong fault zone, has the potential pregnant ability of moderately to strong earthquakes, and might be regarded as seismogenic structure of the 1963 Luobei M 5.8 earthquake based on the synthesized the seismology and satellite image interpretation and field geological investigation results.

关 键 词：依兰-伊通断裂带 太平沟断裂 萝北5.8级地震 发震构造 

分 类 号：P315.2[天文地球—地震学]