Automated detection of slow slip events within the Nankai subduction zone
Article first published online: 14 JAN 2011
Copyright 2011 by the American Geophysical Union.
Geophysical Research Letters
Volume 38, Issue 1, 16 January 2011
How to Cite
2011), Automated detection of slow slip events within the Nankai subduction zone, Geophys. Res. Lett., 38, L01311, doi:10.1029/2010GL045899., , , and (
- Issue published online: 14 JAN 2011
- Article first published online: 14 JAN 2011
- Manuscript Accepted: 7 DEC 2010
- Manuscript Revised: 2 DEC 2010
- Manuscript Received: 19 OCT 2010
- slow slip event;
- automated detection;
- slow earthquake
 We have developed a new automated method for the identification and location of slow slip events (SSEs) during episodic tremor and slip (ETS) in the Nankai subduction zone without any tremor information. SSE models are estimated from continuous tilt data using the Kalman filter algorithm and a grid search, and are eventually identified through statistical evaluations. We applied this method to data recorded for two years in Shikoku, Japan and successfully detected four SSEs coincident with major tremor bursts. Before the onset of SSEs, precursory minor tremor activities usually occur around the fault where SSEs are subsequently detected when tremor migrates into the SSE faults. This suggests that an ETS episode begins with geodetically undetectable small slip around the main fault and grows to a detectable SSE. Such evolution of SSE and tremor activity would reflect the spatial change in the slip property on the plate interface.