Locations of Site 436 and Site C0019 and lithologic zonation of DSDP Site 436. (a) Locations of Site 436 (DSDP Leg 56) and Site C0019 (IODP Expedition 343) (J-FAST) (red triangles). Orange contour lines at 4-m intervals show the coseismic slip displacement of the 2011 Tohoku earthquake off the Pacific coast of Japan, as compiled from Ozawa et al. (2011). The yellow star denotes the epicenter of the mainshock, and gray circles are the aftershocks and the largest foreshock. The blue line shows the Japan Trench. (b) Lithologic zonation of DSDP Site 436 (modified from Shipboard Scientific Party 1980). The drilling depth was 397.5 m below sea floor (mbsf) at this site. Core 38 (blue line) and Core 40 (red line) used in this study were recovered from 358 and 376.8 mbsf, respectively.