Application of gravity exploration in urban active fault detection

Abstract

Active faults are a major source of danger for destructive earthquakes. It is an important task for urban earthquake disaster prevention to find out the spatial location and structural attributes of active faults. At present, the most effective geophysical exploration method for detecting and locating urban concealed active faults is shallow seismic exploration, while other geophysical exploration methods are seldom used. In the detection of active faults in Shanghai, seismic exploration is greatly influenced by human factors in urban areas and the efficiency is low. In this paper, through the comparison and analysis of the alignment of seismic and gravity, it is found that the interpretation results of gravity exploration have a good correspondence with the fault structures interpreted by shallow seismic exploration. At the same time, gravity method reveals that there may be other fault anomalies near the fault anomalies identified in previous literature. It illustrates the effectiveness and feasibility of high-precision gravity detection methods in the detection of urban active fault, and also provides important reference significance for active fault detection in other regions.