Abstract：Taking the nearly three slow slip events(SSE) in Boso Peninsula in Japan in 2011, 2013-2014, and 2018 as examples, we use the independently developed GPS coordinate time series analysis(GTSA) software to batch process the coordinate time series data of multiple GPS stations in the peninsula for a total of 10 a from 2009 to 2019, and build a coordinate time series model containing periodic SSE. The results show that: 1) The mathematical characteristics of the hyperbolic tangent function are very consistent with the motion law of SSE. At the initial stage, the hyperbolic tangent function accelerates slowly, then slides rapidly, and finally decelerates slowly to return to the steady state; 2) The precise modeling of SSE by the function can effectively determine the center of SSE occurrence time, duration, and surface displacement; 3) The duration of SSE in 2011 can reach 50 d at most, and in 2013-2014 and 2018 can reach 25 d at most; 4) The horizontal displacement of the three SSE is toward the southeast, and the elevation displacement is shown as subsidence. The maximum horizontal displacement of the SSE in 2018 was 5.2 cm, and the maximum elevation displacement in 2013-2014 was 3.8 cm.
