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Figure F6. Strain at the time of and following magnitude 7.2 and 7.5 earthquakes beneath the Nankai Trough off Kii Peninsula, Japan (star), reflected in aftershocks in the near vicinity of the earthquake (filled circles in A and B) and in a rise in formation-fluid pressure observed at an ACORK located 220 km from the epicentral area (red line in B). Far-field strain estimated from the seismic moment (volumetric strain shown as contours in A) is far less than inferred from either the coseismic or postseismic pressure increase (secondary axis in B). A smaller but similar signal was observed at the time of a very low frequency earthquake cluster off Cape Muroto (open circles in A) (from Davis et al., 2009). A secular trend of roughly 1.7 kPa/y (0.3 ?strain/y) is also present but has been removed in this plot.

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