Tremor reveals stress shadowing, deep postseismic creep, and depth‐dependent slip recurrence on the lower‐crustal San Andreas fault near Parkfield

摘要: [1] The 2003 magnitude 6.5 San Simeon and the 2004 6.0 Parkfield earthquakes induced small, but significant, static stress changes in lower crust on central Andreas fault, where recently detected tectonic tremor sources provide new constraints deep fault creep processes. We find that these affect rates very differently, consistent with their differing transferred shear stresses. The event appears to have cast a “stress shadow” north of Parkfield, activity was stifled for 3–6 weeks. In contrast, earthquake dramatically increased both south allowing us track postseismic slip. Following this event, initially by up two orders relatively shallow closest rupture, some persisting above background more than year. also observe strong depth dependence recurrence patterns, shallower generally exhibiting larger, less-frequent bursts, possibly signaling transition toward steady increasing temperature depth.