Seismc Inversion of the June 2017 Maoxian Landslide

On 23 June 2017, an extremely large landslide occurred in Maoxian, Sichuan province, resulting in 73 deaths, 10 missing and 3 injured. Large and rapid landslides, generating seismic waves strong enough to be detected by seismometers, can be analyzed for their single-force mechanisms. With the seismograms of 7 broadband stations within 175 km, we investigated the temporal process of the landslide with and without the limitations of the slide direction. The average masses estimated from single-station inversion and multiple-station inversion are both much less than that from the field investigation after the landslide. It may indicate that only a small part of the slip mass was instable, which drived the landslide during the whole process. The direction and duration of the flow can be well determined. The flow, lasting for about 100s, contains 2 sub-events. Some discussions are made on the apparent friction, instantaneous velocity and acceleration based on proportion of induced mass to overall quality. We also estimated the moment tensor solution and source time function by regarding the landslide as a natural earthquake. Results based on single-force mechanisms and double-couple mechanisms are also compared.