MARGINS/GeoPRISMS Post-Doctoral Fellowship Research: Evolution of Sediment Physical Properties in the Nankai Subduction Zone and Implications for the Updip Limit of Seismogenesis

Pennsylvania State Univ University Park, University Park PA

Investigators

Abstract

Abstract Funds are provided for a post-doctoral study of deformation and slip behaviors in subduction systems by an experimental approach combined with seismic data and microstructure observations. The PIs will conduct friction experiments on smectite and illite at elevated temperature and measure the acoustic wave velocities on sediment core samples at different stress states. Results of the friction experiments will be used to further test the hypothesis of smectite-illite transition for updip limits of seismicity. The measurements of acoustic wave velocities at different stress states will allow the PIs to estimate the in-situ stress states and pore pressure in subduction systems by incorporating with seismic data. Samples and data from the IODP NanTroSEIZE transect area will be used to investigate the in situ stress and pore pressure conditions. Broader Impacts The award will support a young female researcher as a MARGINS/GeoPRISMS postdoctoral fellow. The proposed research aims to understand the evolution of slip behavior at the upper limit of the seismogenic zone and the deformation mechanisms in subduction zone fault systems and accretionary prisms. The focal points of the proposed study are also aligned with key questions of the Subduction Cycles and Deformation initiative within the new GeoPRISMS program. Understanding the mechanics and in situ conditions of faulting deformation at subduction plate boundaries has both scientific and social significance in terms of earthquake prediction and disaster prevention.