[SSS04-P27] Quality control of tilt and strain data for automated detection of slow slip events within the Nankai subduction zone, Japa
In this study, we evaluate temporal changes in noise levels of geodetic data. We assumed that continuous geodetic data contains background linear trend, random-walk noise and white noise, and estimated the noise strengths for a 30-day moving time-window using maximum likelihood method. Typical strengths of the random-walk and white noises are approximately 1.0-5.0 nrad/hr0.5 and 1.0-5.0 nrad, respectively, for tilt data, and 0.5-1.0 nstrain/hr0.5 and 0.5-1.0 nstrain, respectively, for strain data. The random-walk noise strengths of tilt data at MASH station in Kii Peninsula had been 1.0-2.0 nrad/hr0.5 and almost constant from 2001 to 2012. They were increasing in 2013 and reached 10-20 nrad/hr0.5. This increase in noise levels lowered the detection capability for SSEs in Kii Peninsula.
This work was supported by JSPS KAKENHI Grant Number JP16H474.