Fig. 13

Thermal and metamorphic environment of the Japan Trench. a Amount of water released upward from subducted sediments and the oceanic crust as estimated by Hyndman and Peacock (2003). For the details of the fluid flux estimation, see Hyndman and Peacock (2003). The green areas indicate the locations of the slow-earthquake-genic regions. b Thermal structure of the Japan Trench as estimated by Peacock and Wang (1999). This panel is adapted from Hyndman and Peacock (2003). The green sections of the plate interface indicate the locations of the slow-earthquake-genic regions. The question mark indicates the possible deep slow-earthquake-genic region. c Pressure–temperature paths for the top of the subducting oceanic crust in the Japan Trench, Nankai Trough, and Cascadia subduction zone (Peacock and Wang 1999; Peacock 2009). The pressure–temperature ranges of the slow-earthquake-genic regions are shown by the green sections of the pressure–temperature paths. The question mark indicates the possible deep slow-earthquake-genic region in the Japan Trench. Metamorphic conditions of the subducting oceanic crust (Peacock 2009) are also shown. eA, epidote–amphibolite; eB, epidote–blueschist; egA, epidote–garnet–amphibolite; jeB, jadeite–epidote–blueschist; laE, lawsonite–amphibole eclogite, PA; prehnite–actinolite; PP, prehnite–pumpellyite; and Z, zeolite facies