[M-IS22] [JJ] Drilling Earth Science

[MIS22-18] Progress in Bend-Fault Hydrology in the Old Incoming Plate (H-ODIN) project

*Tomoaki Morishita¹, Makoto Yamano², Gou Fujie³, Shigeaki Ono³, Jun-Ichi Kimura³, Koichiro Obana³, Yasuyuki Nakamura³, Asuka Yamaguchi⁴, Takanori Kagoshima⁴, Saneatsu Saito³, Shuichi Kodaira³, Jason Phipps Morgan⁵ (1.Kanazawa University, 2.ERI, Univ. Tokyo, 3.JAMSTEC, 4.AORI, Univ. Tokyo, 5.Univ. London)

Keywords:Drilling project into plate bending-induced normal faults, Northwest Pacific region

Hydration due to plate bending-induced normal faults (bend-faults) in the region between the trench axis and outer rise (outer rise) has recently drawn considerable attention (e.g., Grevemeyer et al., 2007; Fujie et al., 2013). In order to deepen our understanding of bend-fault hydration, we have submitted an IODP pre-proposal: Bending fault hydrology of the Old Incoming Plate (H-ODIN). We also organized an IODP workshop, Bend-Fault Serpentinization, in London, 2016, sponsored by CHIKYU IODP Board, the UK-IODP, and ECORD. We refined drilling purpose, drilling site and drilling strategy for Northwest Pacific region (Old-Cold subduction) and Middle Amercia region (Young-Hot subduction) in the workshop, because it is ideal to compare subduction zones in several contrasting geodynamic states (e.g. Old plate vs Young plate, Horst-and-graben bend-fault structures are well developed in the northwestern Pacific subduction system. We will present our progress in the proposals.