Abstract:

Ground penetration radar, luminescence dating and radon measurement were used to detect the Xilingang fault in Pearl River Delta. The results illustrate that during the Late Pleistocene epoch, at least two paroxysmal fault movements happened in the research area. The first movement happened about 40 000a ago, causing a block inclination of hanging wall, and an unconformity interface among the Quaternary strata; the slip of the fault reached to 5.5 m. The second paroxysmal movement, which happened 20 000a ago, causing the fault slip about 0.53 m. The peak value of radon on the fault is three times higher than the background value. All the evidences demonstrate that the Xilingang fault is active and has potential dange, therefore the conclusion that the faults located in the north of Pearl River Delta were non-active and steady should be changed.

Key words: Quaternary fault, fault activity estimation, ground penetration radar, Xilingang area