主-被动源地震面波勘探方法在岩溶区浅覆盖层探测中的应用  

Application of active and passive-sourced seismic surface wave exploration to the detecting of shallow overburden karst area

作　　者：张伟[1,2] 吕勇 梁东辉[1,2] 邬健强 刘伟[1,2] 朱超强 ZHANG Wei;LYU Yong;LIANG Donghui;WU Jianqiang;LIU Wei;ZHU Chaoqiang(Institute of Karst Geology,Chinese Academy of Geological Sciences,Guilin 541004,Guangxi,China;Key Laboratory of Karst Dynamics,MNR&GZAR,Guilin 541004,Guangxi,China)

机构地区：[1]中国地质科学院岩溶地质研究所,广西桂林541004 [2]自然资源部广西岩溶动力学重点实验室,广西桂林541004

出　　处：《地质通报》2022年第2期416-424,共9页Geological Bulletin of China

基　　金：中国地质调查局项目《桂东北岩溶系统基础地质调查》(编号:DD20190022);《西南岩溶区15万填图试点》(编号:DD20160061)。

摘　　要：采用主-被动源地震面波勘探方法,对桂林市兴安县典型浅覆盖层实验区三维地质结构进行探测研究。结合主-被动源面波数据提取的频散曲线,拓宽了频带,提升了低频信号的分辨率。实验结果显示,测区内地下介质横波速度值范围为161.5~519.5 m/s,根据速度值的差异将实验区地下介质大致分为4个层位,第一层速度范围为161.5~281 m/s,第二层速度范围为281~360.5 m/s,第三层速度范围为360.5~400.2 m/s,第四层速度范围为400.2~519.5 m/s。结合钻孔资料,对应的第一层岩性为粘土层,第二层为粉砂质粘土,第三层为细砂-砂砾岩,第四层为灰岩,且局部土洞、溶洞等构造发育。研究结果表明,瑞雷面波勘探方法能够较准确地刻划浅覆盖层地下介质土层厚度、结构分布及土层与基岩面接触带起伏形态。The active and passive-sourced seismic surface wave exploration was carried out to study the three-dimensional geological structure of the typical shallow overburden area in Xing'an County,Guilin City.The dispersion curve extracted from active and passive surface wave data broadened the frequency band and improved the resolution of low-frequency signals.The experimental results show that the shear wave velocity of underground medium ranges from 161.5 m/s to 519.5 m/s in the survey area.According to the difference of velocity value,the underground medium in the experimental area is roughly divided into four layers.The velocity of the first layer ranges from 161.5 m/s to 281 m/s,the second from 281 m/s to 360.5 m/s,the third from 360.5 m/s to 400.2 m/s,and the fourth from 400.2 m/s to 519.5 m/s.Combined with the drilling data,the lithology of the above-mentioned four layers corresponds to clay,silty clay,sand to glutenite,and limestone,respectively;and some local structures such as soil caves and karst caves are locally developed.The research results show that the Rayleigh surface wave exploration method can more precisely describe the soil thickness,structure distribution and the undulating shape of the contact between the soil layer and the bedrock.

关 键 词：瑞雷面波 岩溶区 浅覆盖层 土层厚度 结构分布 地质调查工程 

分 类 号：P631.4[天文地球—地质矿产勘探]