Fig. 4: Interpretation of the Okhotsk earthquake and modified slab model.
From: Two-stage rupture during the Mw 8.3 Okhotsk 2013 deep-focus earthquake constrains slab geometry
The subducted slab forms folds at about 600 km, and the folds curvature diminishing progressively toward the south. The earthquake primarily occurred within the folded MOW, propagating horizontally first and then vertically downward (blue arrow). The thick blue line is the plate boundary70. Dark red arrows show the viscous drag reduction of the upper mantle, that induces a transient slab plunge acceleration 1 month before the mainshock53. The bold blue arrow shows the accelerated slab plunge since the great deep earthquake58. The cyan dots are Kamchatka catalog33. The insert shows the study area. The insert panel (a) shows the cumulative energy of the back-projection matrix over a 36-s time window projected onto the horizontal and vertical planes.
