Fig. 4
From: Two long-term slow slip events around Tokyo Bay found by GNSS observation during 1996–2011
Seismicity of shallower earthquakes near Faults A and B. a Epicenters of earthquakes that occurred at depths of 0–100 km during 1996–2011. Faults A and B are identical to those in Model D2 determined by the inversion (Fig. 3f). The circles denoted by A1 and A2 represent the areas where seismic activation and quiescence anomalies, respectively, were present between 2005 and 2008 (Katsumata and Sakai 2013). Fault C represents a previously proposed hypothetical fault. b The events that occurred at depths of 20–30 km, taken to calculate the background seismicity, are surrounded by the dashed lines. c The blue curve denotes the cumulative number of declustered events in Region A′ in (b). In the red curve, the average rate during 1998–2002 is subtracted from the blue curve. The numbers of these events are shown by the left (N) and right (ΔN) vertical axes, respectively. d The blue curve denotes the cumulative number of declustered events in Region B′ in (b). In the red curve, the average rate during 1996–2011 is subtracted from the blue curve. The dashed lines during 1996–2001 and 2009–2011 have the same slope and are superimposed for easier comparison. The anomaly marked in yellow might be related to the SSE found by Kobayashi and Hirose (2016)