[SSS12-P06] Relationship between plate boundary temperature and shallow slow earthquakes off Kii Peninsula and Hyuga
Keywords:shallow slow earthquakes, bottom-simulating reflector, temperature
Formation of methane hydrate is constrained by temperature and pressure conditions and thus methane hydrate BSRs can be an indicator of subseafloor temperature. BSRs are present in the wide range of the Nankai accretionary prism and the forearc basins. Therefore, we can widely estimate the plate boundary temperature from BSR depths. As a result of comparison between plate boundary temperature and VLFEs/tremors, we find VLFEs and the tremors begin to occur at around 50°C along the plate boundary fault. This may imply that the regions of VLFE and tremor occurrence are dependent on temperature. If so, spatial distribution of upper limit of VLFE and tremor is obtained in the Nankai Trough.