Strong-motion recordings in M_S4.7 Beichuan, Sichuan earthquake on October 22, 2020

On October 22, 2020, an earthquake with magnitude 4.7 occurred in Beichuan County, Sichuan Province. 532 sets of three-component acceleration records have been obtained by Sichuan strong motion network, which contribute to the study of regional ground motion attenuation and ground motion characteristics. After the conventional processing of strong motion records, the relevant parameters of strong motion records have been calculated. The spatial distribution maps of PGA and PGV are obtained by Kriging interpolation method, and the long axis is NE-SW direction. The attenuation law of PGA and PGV of strong motion records with distance is analyzed. Through comparison and analysis with three commonly used attenuation relationship prediction values, such as attenuation relationship of Eastern strong earthquake area established by the fifth generation zoning map, it can be seen that PGA and PGV of strong motion records are similar to those of this earthquake. The attenuation characteristics of the model are in good agreement with the attenuation relationship of horizontal bedrock acceleration proposed by Yu and Wang (2006). The dense strong motion records obtained from the Beichuan M_S4.7 earthquake provide important data support for establishing regional attenuation relationships and carrying out studies based on the empirical Green function method (EGFM) to reproduce the distribution of strong ground motions of large earthquakes.