Abstract Seismic phase observation reports and seismic waveform data are selected from the California Institute of Technology and US Geological Survey and the Southern California Earthquake Data Center. Relocated hypocenters of MW6.4 foreshock and MW7.1 mainshock of Ridgecrest earthquake and its aftershocks with MW≥2.5 within one month after the earthquake are independently and jointly inversed using double-difference location algorithm combined with the waveform cross-correlation technique. The relocation results show that four event clusters are formed from 2 098 events, and seismic source parameters with a relocation rate of up to 97% are achieved. The travel time residual and cross-correlation travel time residual of earthquake sequences decreases to 65 ms and 57 ms, respectively. Compared with the original result, the linear features of the epicenter are more significant after relocation, with aftershocks forming an L-shaped and T-shaped pattern, respectively. The length of aftershocks is about 90 km and the width is about 25 km. The relationship between seismic activity and fault structure is quantitatively analyzed and the results state that the Ridgecrest earthquake sequence starts deep and propagates to the shallow surface gradually. The predominant range of depth distribution is from 4 km to 8 km, showing the characteristics of segmented bands, revealing that the Ridgecrest sequence destroyed the complex fault system composed of multi fault structures with different scales, and the Little lake fault zone is the seismogenic fault of the Ridgecrest earthquake sequence.
HUANG Xiaomei,CHEN Qiang,ZHANG Yijun et al. Analysis of the July 2019 Ridgecrest Earthquake and Aftershocks Using Double-Difference Relocation[J]. jgg, 2021, 41(8): 858-864.
HUANG Xiaomei,CHEN Qiang,ZHANG Yijun et al. Analysis of the July 2019 Ridgecrest Earthquake and Aftershocks Using Double-Difference Relocation[J]. jgg, 2021, 41(8): 858-864.
