Quaternary activity of Shawan fault in Pearl River delta

The Shawan fault is one of the most important faults in Pearl River delta. To explain the Quaternary activity of Shawan fault, the authors conducted a series of work, such as 1:50000 geological mapping, chronological study, determination of radon, shallow seismic reflection and combined drilling verification. According to the analysis of Quaternary geomorphology and fracture coupling as well as the characteristics of historical seismic reflection, the fault is still active. Field survey and shallow seismic reflection show that the fault didn't cut Quaternary strata, and radon measurement also shows that the intensity of the fault activity is weak; ESR chronology shows that the activity intensity was relatively strong before late Pleistocene, and afterward it became weak; tectonic analysis of Luohanshan indicates that local area of Luohanshan was in a tension environment, but activity intensity has become weaker and weaker since late Holocene. In short, Shawan fault is still active, but the intensity is weak.