高密度电法探测第四纪玄武岩覆盖区断裂及其活动性分析——以鸭绿江断裂带抚松段西支断裂为例  

Detecting Active Faults in Quaternary Basalt Areas by the High-Density Electrical Method:An Example of the West Branch of the Fusong Section of Yalüjiang Fault Zone in Northeast China

作　　者：李嘉瑞 马秀敏[1] 姜自忠 王磊 庞博 杨程博 LI Jiarui;MA Xiumin;JIANG Zizhong;WANG Lei;PANG Bo;YANG Chengbo(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081;China University of Geosciences(Beijing),Beijing 100083;Department of Natural Resourrces of Changbai Mountain Protection&Development Zone Management Committee Chinan District Management Committee,Baishan,Jilin 134512;Liaoning Geological andMineral Research Institute CO.,LTD,Shenyang,Liaoning 110032;The Fourth Geological Survey Institute of Jilin Province,Tonghua,Jilin 134001)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]中国地质大学(北京),北京100083 [3]吉林省长白山保护开发区池南区管理委员会自然资源局,吉林白山134512 [4]辽宁省地质矿产研究院有限责任公司,辽宁沈阳110032 [5]吉林省第四地质调查所,吉林通化134001

出　　处：《地质与勘探》2022年第1期118-128,共11页Geology and Exploration

基　　金：中国地质调查局地质调查项目(编号:DD20190546、DD20190290)资助。

摘　　要：覆盖区活动断裂探测往往需要选择合理的物探方法以确定断裂位置,高密度电法具有数据采集效率高、探测精度高等优点,已在覆盖区活动断裂探测中得到广泛应用。本文利用高密度电法在长白山玄武岩覆盖区进行断裂探测,对实测数据进行反演,分析了NE向鸭绿江断裂带抚松段西支断裂在松江河镇北东侧第二松花江畔的展布形态,同时,利用钻探对断裂探测结果加以验证。视电阻率剖面表明完整基岩主要呈现出高阻值,断裂破碎带由于含水丰富则呈现为低视电阻率异常值。而断层内较为破碎,且富含水,故在视电阻率剖面上呈现明显低阻异常,这些结果能够与钻孔揭露地层实物资料较好对应。钻孔的断层样品^(14)C测年结果显示,西支断裂在松江河镇兴隆林场为晚更新世活动断裂。Detection of active faults in coverage areas requires the selection of proper geophysical methods to determine the location of fault.The high-density electrical method with the advantages of high efficiency in data acquisition and high detection accuracy has been widely used in the detection of active faults in such areas.In this work the high-density electrical method was employed to detect the faults in the basalt area of the Changbaishan Mountains.The measured data were inverted to analyze the distribution pattern of the west branch of the Fusong segment of the NE-trending Yalüjiang river fault zone along the second Songhua River in the northeast of Songjianghe Town.At the same time,the fault detected was verified by drilling.The apparent resistivity profile shows that the intact bedrock mainly exhibits high resistance values,and the fractured zone of the fault presents low apparent resistivity anomalies due to its rich water content.The interior of the fault is relatively broken and rich in water,so its obvious low-resistivity anomalies appear in the apparent resistivity profile.These results corresponded well to the formation revealed by the boreholes.The ^(14)C dating on the fault samples from the boreholes shows that the west branch of the fault was active in the Late Pleistocene in the Xinglong forest farm of Songjianghe Town.

关 键 词：高密度电法 长白山地区 玄武岩覆盖区 鸭绿江断裂带 断裂活动性分析 

分 类 号：P315.2[天文地球—地震学]