My research interest is infrequent catastrophic hazards from earthquakes and tsunamis in a geologic time scale. Such hazards can be assessed using sedimentary data of tsunami deposits, which are typically preserved in coastal sedimentary sequences. Tsunami deposits benefit numerical modeling of past tsunamis that improve our understanding on generation mechanisms of the low-frequency large-scale earthquakes and tsunamis. The photo shows the work to excavate a columnar sediment sample at Guerrero, Pacific coast of Mexico, for searching paleotsunami deposits.
I am working on numerical modeling of processes of tsunami-induced erosion, transport and deposition of sediments and resulting morphological change. Such study is used for searching and identifying paleotsunami deposits and deposit-based modeling of past earthquakes and tsunamis. The groundbreaking data acquired after the 2011 Tohoku earthquake and tsunami, which is an advantage to work in Tohoku, is applied to validate numerical simulations. The image shows the result of tsunami sediment transport modeling of the 1867 Keelung earthquake in the northern Taiwan (modified after Sugawara et al., 2019).
Sugawara, D., Yu, N.T., Yen, J.Y., Estimating a Tsunami Source by Sediment Transport Modeling: A Primary Attempt on a Historical/1867 Normal-Faulting Tsunami in Northern Taiwan. Journal of Geophysical Research: Earth Surface 124, 1675-1700, 2019. doi:10.1029/2018JF004831
Sugawara, D., Evolution of numerical modeling as a tool for predicting tsunami-induced morphological changes in coastal areas: A review since the 2011 Tohoku Earthquake, In: Santiago-Fandino, V., Sato, S., Maki, N., Iuchi, K., eds., The 2011 Japan Earthquake and Tsunami: Reconstruction and restoration. Insights and Assessment after 5 Years. Advances in Natural and Technological Hazards Research 47, Springer, Japan, 451-467, 2018. doi:10.1007/978-3-319-58691-5_26
Chagué, C., Sugawara, D., Goto, K., Goff, J., Dudley, W., Gadd, P., Geological evidence and sediment transport modelling for the 1946 and 1960 tsunamis in Shinmachi, Hilo, Hawaii. Sedimentary Geology 364, 319-333, 2017. doi:10.1016/j.sedgeo.2017.09.010
Yamashita, K., Sugawara, D., Takahashi, T., Imamura, F., Saito, Y., Imato, Y., Kai, T., Uehara, H., Kato, T., Nakata, K., Saka, R., Nishikawa, A., Numerical simulations of large-scale sediment transport caused by the 2011 Tohoku earthquake tsunami in Hirota Bay, southern Sanriku Coast. Coast. Eng. J. 58 (4), 1640015., 2016. doi:10.1142/S0578563416400155
Minoura, K., Sugawara, D., Yamanoi, T., Yamada, T., Afftereffects of Subduction-Zone Earthquakes: Potential Tsunami Hazards along the Japan Sea Coast. Tohoku Journal of Experimental Medicine 237, 91-102, 2015. doi:10.1620/tjem.237.91