Abstract：This article summarizes the site selection, instrument configurations and installation of temporary seismic network deployment, and analyzes the initial seismic characteristics of the 2022-06-01 MS6.1 Lushan earthquake ambient noise and the aftershock sequence from the network. The results show that after the temporary seismic stations were deployed, the density of seismic stations in earthquake region is improved, and that the joint network with the permanent seismic stations improves the azimuthal coverage of the seismic stations and the spatial resolution of the scientific research. Under the influence of nearby cultural noise sources, the temporary stations generally show higher noise level than the nearby permanent station, and the noise level is significantly higher than the average value of NHNM and NLNM; some stations are close to or higher than the NHNM value. The high-frequency noise presents a prominent diurnal variation characteristic related to human activities, that is, seismic noise level increases during the daytime, and decreases at night. Affected by this, the number of earthquakes recorded by temporary seismic network during the daytime is significantly less than nighttime, and the number of small earthquakes recorded is significantly reduced. The results from hypoDD relocation show that the aftershocks are mainly distributed in the north of the Xiaoguanzi fault, with a northeast distribution, about 10 km long in the northeast and about 6 km in the northwest. The magnitude of completeness MC of aftershock sequence calculated by maximum curvature method is 1.2, the MC increase from 1.1 in the nighttime to 1.4 in the daytime, and this mean the seismic monitoring capacity of the seismic region during the daytime is weakened. We also observed that the aftershock sequence after a medium-strong earthquake decays rapidly with time, and the number of aftershocks within 5 days is about 80% of the total aftershocks, especially those within 2 days after the mainshock. In order to better understand the development process of earthquakes, it is necessary to ensure the rapid and effective deployment of seismic stations to give play to the effectiveness of seismic stations.
LIN Liping,WANG Yuhang,WU Peng et al. The Temporary Seismic Network Deployment and Aftershock Sequence Observation of the 1 June 2022 MS6.1 Lushan Earthquake[J]. jgg, 2024, 44(2): 195-201.
