微动勘探技术在城市地面沉降检测中的应用研究  

Application of microtremor survey method in detection of urban land subsidence

作　　者：徐浩 吴小平[1] 盛勇[2] 廖圣柱[2] 贾慧涛 徐子桥 XU Hao;WU Xiao-Ping;SHENG Yong;LIAO Sheng-Zhu;JIA Hui-Tao;XU Zi-Qiao(School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China;Anhui Institute of Geophysical and Geochemical Prospecting Techniques,Hefei 230022,China)

机构地区：[1]中国科学技术大学地球与空间科学学院,安徽合肥230026 [2]安徽省地球物理地球化学勘查技术院,安徽合肥230022

出　　处：《物探与化探》2021年第6期1512-1519,共8页Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(41874084)。

摘　　要：城市地面沉降极易导致地面裂缝甚至塌陷,引发安全事故。城市环境中,人文干扰强烈,安全、环保要求高,导致传统物探方法无法在城市中有效开展。微动勘探技术是一种无源、高效、环境友好的物探方法,且能够在城市强干扰环境下对地下地质情况进行探测。选取合肥市谢岗小学作为研究场地,重点探究微动方法在地面沉降原因探测方面的适用性和有效性。根据采集到的微动数据,采用F-K法进行频散曲线提取,再进行反演得到地下横波速度结构,进而了解地下地质情况,最后采取钻探进行验证。研究结果表明:微动勘探技术可以有效地探测出地下不密实土体的位置、规模等信息,从而排除沉降区二次事故的发生。Urban land subsidence is liable to induce ground fractures or even collapse,thus causing safety accidents.However,traditional geophysical methods cannot be applied in cities due to the strong human interference and high requirements for safety and environmental protection in the urban environment.The microtremor survey method is a passive,efficient,and environment-friendly geophysical method and it can be used to detect the underground geological conditions in the urban environment with strong interference.Taking Xiegang Primary School in Hefei City as the research site,this paper focuses on the applicability and effectiveness of the microtremor survey method in detecting the causes of land subsidence.Based on the microtremor survey data collected,the dispersion curve was extracted using the F-K method and then the underground shear wave velocity structure was obtained through inversion,thus revealing the underground geological conditions.Finally,verification was conducted through drilling.The results show that the microtremor survey is an effective geophysical method for detecting the information such as the position and scale of underground unconsolidated soil,and thus the secondary accidents in subsidence areas can be eliminated.

关 键 词：微动勘探 城市地面沉降 不密实体 沉降原因 F-K法 城市地质 

分 类 号：P631.4[天文地球—地质矿产勘探]