Plate bending at a trench leads to ‘bend-fault serpentinization’ (BFS) reactions in cold lithospheric mantle and crust, with profound implications for exchange of carbon and water between Earth’s exosphere and mantle. BFS favours chemosynthesis, hence bend-faults could host a major unseen component of the deep biosphere. This workshop is needed to develop a Chikyu-based IODP proposal(s) to study BFS in the regions targeted by the BFS and H-ODIN IODP pre-proposals.

A key outcome of the workshop will be to move forward on organizing, coordinating, and writing a full-proposal(s) on bend-fault serpentinization. Another priority is to inform and engage new members in marine bio- and geo-sciences. Because of the youth and breadth of integrated science in this field, we have also decided that a dual-purpose workshop would best suit the community’s needs.

The first part of the workshop will be a short 1 day long conference that will be the first specialized conference on Bend-Fault Serpentinization as a marine geological process – with discussion of both the Japan Trench and Middle America Trench exemplars of Bend-Fault Serpentinization.

The second part would be a follow-on focused 2 day long planning workshop that involves ~30-45 members of the first meeting. This group would be tasked with the development of a consensus framework for drilling-led study of bend-faulting, bend-fault hydrothermalism, bend-fault serpentinization processes, and the bend-fault biome in two contrasting tectonic environments.

The workshop is supported by JAMSTEC(CIB), UK-IODP, and ECORD.