Rapid and accurate positioning concealed fault using geophysical and geochemical techniques in cities and surrounding areas——A case study of Lingui District, Guilin City, Guangxi

This paper is the result of hydrogeological survey engineering.

Objective The detection of concealed fault structure in the city and its surrounding areas has an important impact on urban construction and economic development, which has attracted people's attention. According to the geological background and human conditions of the city, the key to the rapid and accurate location of concealed fault is to adopt appropriate methods, which must have the characteristics of rapid economy, green environmental protection and strong anti-interference ability.

Methods Taking Lingui District of Guilin city as an example, in order to quickly and accurately locate the concealed fault F1 covered by the quaternary system, according to the geological background and the characteristics of the surface landscape of the District, a comprehensive geophysical and geochemical exploration method, such as CSAMT, soil mercury gas measurement, radon gas measurement, is adopted.

Results It is found that the low resistivity anomaly is highly consistent with the high value anomaly of soil mercury gas and radon gas, It is speculated that the location of the multi method abnormal coincidence is the location of the concealed fault, and through drilling verification, the concealed fault structure and rich groundwater are exposed, which provides a basis for the search and development of deep geothermal water in this area.

Conclusions It is obvious that CSAMT, soil mercury gas measurement and radon gas measurement are the technical combination to realize the rapid and accurate location of concealed faults in Guilin and its surrounding areas, and also provide reference for the detection of concealed faults in other areas.