Deep low‐frequency tremors as a proxy for slip monitoring at plate interface

Abstract

We propose a new method to monitor slip at the plate interface using non‐volcanic deep‐low frequency (DLF) tremors. We assume that a DLF tremor is the superposition of frequently excited intermittent events, meaning that the envelope of the reduced displacement of the DLF tremor provides an apparent moment rate function. We estimate a conversion factor from the apparent moment to the seismic moment with an assumption that a total size of DLF tremors of an episode is proportional to the size of corresponding slow slip event (SSE). The cumulative seismic moment estimated by DLF tremors is consistent with that estimated from geodetic methods and provides appropriate slip and slip rate at the plate interface. This proves our assumptions and demonstrates that DLF tremors are useful tool for real‐time monitoring of the slip at the plate interface.