Dr. Masumi Yamata, Assistant Professor at Kyoto University, presents "Repeating Seismic Events Indicate Stick-slip Behavior Before a Landslide" at the MIT Earth Resources Laboratory on February 19, 2016.
The characteristics of seismic signals generated by the mass movement are considered to reflect the property of the sliding surface, and the use of seismic data for landslide study attracts more attention recently. Here we analyzed the seismic data associated with 2015 Rausu landslide. A seismogram near the landslide recorded curious intermittent tremors one day before the substantial mass movement. Each tremor has almost identical waveforms, and the amplitude increases linearly as a function of time. This tremor sequence is an evidence of the stick-slip movement of the landslide before the large failure occurs. This is an important observation suggesting that the heterogeneous structure such as asperities on the slip surface play an important role to control the movement of landslide.
