This is a proposal to complete a coordinated series of laboratory analyses of the properties and composition of sediments recovered from the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) drilling by the Integrated Ocean Drilling Program. The proposed work will generate laboratory data needed to test the core hypotheses of NanTroSEIZE, particularly as they relate to fault strength, pore pressure, and fault sliding stability. The work will produce comprehensive datasets describing mechanical and transport properties, lab-based constraints on in situ pore pressure and permeability within a fault system that generates great earthquakes and tsunamis, and integration of datasets to better understand how fluids, grain fabric, and mineral composition combine to modulate fault behavior.
Broader Impacts The results will be broadly applicable to understanding fault strength, slip behavior, and pore pressure generation in seismogenic fault zones of all types. Societal relevance of NanTroSEIZE work is very strong. The project will support seven graduate students, several of whom were selected to sail during Stage 1 as shipboard scientists. It will also support several undergrads as lab assistants and for senior theses. Lab work will provide valuable data for the rest of the NanTroSEIZE research community, build a scientific foundation for planning forthcoming riser drilling, and generate considerable interest within the global fault-zone-drilling community. Outreach programs through IODP, CDEX, and JOI E&O structure.