Last Update 02/08 2011
Research: Knowledge of the subsurface temperature structure is important for studies of physical and chemical processes in convergent plate boundary zones. We have been studying the thermal structure of subduction zones through measurement of terrestrial heat flow on the surface and numerical modeling. The focus of our interest is the temperature distribution along the subducting plate interface that generates large thrust earthquakes, especially in the southwest Japan subduction zone. Most part of this seismogenic zone lies beneath relatively shallow seas, where it is difficult to measure heat flow by ordinary methods because of large temporal variations in the bottom water temperatures. We thus developed pop-up type long-term temperature monitoring instruments and have been trying to determine heat flow by analyzing the obtained temperature records. We are also conducting studies on thermal anomalies around active fault zones and reconstruction of the ground-surface temperature history through detailed temperature measurements in boreholes. Publications: Hyndman, R. D., K. Wang and M. Yamano, Thermal constraints on the seismogenic portion of the southwestern Japan subduction thrust, J. Geophys. Res., 100, 15373--15392, 1995. Wang, K., R. D. Hyndman and M. Yamano, Thermal regime of the Southwest Japan subduction zone: effects of age history of the subduction plate, Tectonophysics, 248, 53--69, 1995. Kinoshita, M. and M. Yamano, Hydrothermal regime and constraints on reservoir depth of the Jade site in the Mid-Okinawa Trough inferred from heat flow measurements, J. Geophys. Res., 102, 3183--3194, 1997. 山野誠・木下正高・松林修・中野幸彦, 南海トラフ付加体の温度構造と間隙流体による熱輸送, 地学雑誌, 109, 4, 540--553, 2000. Yamano, M. and S. Goto, Long-term temperature monitoring in a borehole drilled into the Nojima Fault, southwest Japan, Island Arc, 10, 326--335, 2001. Yamano, M., M. Kinoshita, S. Goto and O. Matsubayashi, Extremely high heat flow anomaly in the middle part of the Nankai Trough, Physics and Chemistry of the Earth, 28, 487--497, 2003. Yamano, M. and S. Goto, Long-term monitoring of the temperature profile in a deep borehole: temperature variations associated with water injection experiments and natural groundwater discharge, Phys. Earth Planet. Inter., 152, 326--334, 2005. Hamamoto, H., M. Yamano and S. Goto, Heat flow measurement in shallow seas through long-term temperature monitoring, Geophys. Res. Lett., 32, L21311, doi:10.102, , 2005. Yamano, M., M. Kinoshita and S. Goto, High heat flow anomalies on an old oceanic plate observed seaward of the Japan Trench, Int. J. Earth Sci., 97, 345--352, 2008. Yamano, M., S. Goto, A. Miyakoshi, H. Hamamoto, R.F. Lubis, Vuthy M. and M. Taniguchi, Reconstruction of the thermal environment evolution in urban areas from underground temperature distribution, Sci. Total Environ., 407, 3120--3128, 2009. |
