综合物探法在城市断层调查中的应用

Application of Comprehensive Geophysical Prospecting Method in Urban Fault Investigation

为查明惠州断裂的延伸范围、倾向及断层性质等信息,将微动面波法、高密度电法及可控源音频大地电磁法用于惠州断裂调查,设计从断裂北侧向南侧依次开展物探工作,根据物探分析成果布置地质勘探孔。结果表明,综合物探方法探测区域断裂构造效果好,高密度电法高低阻交界的等值线密集的区域、横波速度剖面呈条带状向下延伸的低速区,且可控源电阻率剖面向大深度范围延伸的低阻异常区均揭露了断层的存在。分析钻孔取心结果可知物探剖面成果准确,惠州断裂多由碎裂岩带和构造角砾岩带组成,研究成果可为城市地下断层探测研究工作提供参考。

In order to find out the extension range,inclination and fault properties of the Huizhou fault,the micro-moving surface wave method,high-density electrical method and controlled source audio magnetotelligem method are used to investigate the Huizhou fault,and the geophysical exploration work is designed to be carried out from the north side of the fault to the south side,and geological exploration holes are arranged according to the results of geophysical analysis.The results show that the integrated geophysical exploration method has a good effect in detecting regional fault structures,and the existence of faults is revealed in the region where the isoline is dense at the junction of high and low resistance by high-density electrical method,the low-speed area where the shear wave velocity profile extends down in a strip,and the low-resistance anomaly area where the controlled source resistivity profile extends to a large depth range.The analysis of the drilling and coring results shows that the geophysical section results are accurate,and the Huizhou fault is mostly composed of cataclastic rock belt and structural breccia belt.The research results can provide reference for urban underground fault detection research.