Figure 10. Stress drop change among the 3 time periods indicated in Figure 9 using only Mw>1.1 earthquakes. (A1) Difference between pre-Sep 2004 and Sep 2004-Sep 2005 using AS2007 results for comparison with A2. (A2) Difference between pre-Sep 2004 and Sep-2004 and Sep-2005 from this study. (A3) Difference between Sep 2004-Sep 2005 and post-Sep 2005 from this study. Color represents the percentage of log10 stress drop difference of the over stress drop standard deviation to describe stress drop variations over time and space. (B1-B4) Stress drop temporal change in the four regions outlined by dashed curves: I. SAFOD area, II. Creeping Zone, III. 1966 M6 area, IV. Locked zone, where the blue squares are the median stress drop over time calculated from every certain earthquakes (vary by area), and the red error bars describe the range of median stress drops calculated by 30 times of bootstrapping resampling, each resample contains 70% of the earthquakes for each blue square. Two vertical dashed lines mark the 3-month and 1-year after 2004 M6 earthquake.