Name: TAKEUCHI, Nozomu
Position:Associate Professor
Division/Center: Ocean Hemisphere Research Center
Research Area: global seismology

Last Update 12/23 2017


analysis of scattered waves, waveform inversion for 3-D Earth structure, development of accurate methods for computing synthetic seismograms


Cummins, P.R., Geller, R.J. and Takeuchi, N., DSM complete synthetic seismograms: P-SV, sphericallysymmetric, case, Geophys. Res. Lett., 21, 1663--1666, 1994.

Cummins, P.R., Geller, R.J., Hatori, T. and Takeuchi, N., DSM complete synthetic seismograms: SH, sphericallysymmetric, case, Geophys. Res. Lett., 21, 533--536, 1994.

Geller, R.J. and Takeuchi, N., A new method for computing highly accurate DSM synthetic seismograms, Geophys. J. Int., 123, 449--470, 1995.

Takeuchi, N., Geller, R.J. and Cummins, P.R., Highly accurate P-SV complete synthetic seismograms using modified DSM operators, Geophys. Res. Lett., 23, 1175--1178, 1996.

Cummins, P.R., Takeuchi, N. and Geller, R.J., Computation of complete synthetic seismograms for laterally heterogeneous models using the Direct Solution Method, Geophys. J. Int., 130, 1--16, 1997.

Geller, R.J. and Takeuchi, N., Optimally accurate second order time domain finite difference scheme for the elastic equation of motion,, Geophys. J. Int., 135, 48--62, 1998.

Takeuchi, N., Geller, R.J. and Cummins, P.R., Complete synthetic seismograms for 3-D heterogeneous Earth models computed using modified DSM operators and theirapplicability to inversion for Earth structure, Phys. Earth Planet. Inter., 119, 25--36, 2000.

Mizutani, H., Geller, R.J. and Takeuchi, N., Comparison of accuracy and efficiency of time-domain schemes for calculating synthetic seismograms, Phys. Earth Planet. Inter., 119, 75--97, 2000.

Igel, H., Takeuchi, N., Geller, R.J., Megnin, C., Bunge, H.P,Clevede, E., Dalkolmo, J. and Romanowicz, B., The COSY Project: verification of global seismic modeling algorithms, Phys. Earth Planet. Inter., 119, 3--23, 2000.

Takeuchi, N. and Geller, R.J., Optimally Accurate Second Order Time-Domain Finite Difference Scheme for Computing Synthetic Seismograms in 2-D and 3-D Media, Phys. Earth Planet. Inter., 119, 99--131, 2000.

Takeuchi, N., Watada, S., Tsuboi, S., Fukao, Y.,ˇˇKobayashi, M., Matsuzaki, Y.ˇˇand Nakashima., N., Application of Distributed Object Technology to Seismic Waveform Distribution, Seism. Res. Lett., 73, 2, 166--172, 2002.

Takeuchi, N. and Geller, R.J., Accurate Numerical Methods for Solving the Elastic Equation of Motion for Arbitrary Source Locations, Geophys. J. Int., 154, 852--866, 2003.

Takeuchi, N. and Kobayashi, M., Improvement of Seismological Earth Models by Using Data Weighting in Waveform Inversion, Geophys. J. Int., 158, 681--694, 2004.

Takeuchi, N., Finite Boundary Perturbation Theory for the Elastic Equation of Motion, Geophys. J. Int., 160, 1044--1058, 2005.

To, A., Romanowicz, B., Capdeville, Y. and Takeuchi, N., 3D effects of sharp boundaries at the borders of the African and Pacific Superplumes: Observation and modeling, Earth Planet. Sci. Lett., 233, 137--153, 2005.

Cao, A, Romanowicz, B. and Takeuchi, N., An observation of PKJKP: inferences on inner core shear properties, Science, 308, 1453--1455, 2005.

Kawai, K., N. Takeuchi and R.J. Geller, Complete synthetic seismograms up to 2 Hz for transversely isotropic spherically symmetric media, Geophys. J. Int., 164, 411--424, 2006.

Takeuchi, N., Whole mantle SH-velocity model constrained by waveform inversion based on three-dimensional Born kernels, Geophys. J. Int., 169, 3, 1153--1163, 2007.

Kawai, K., N. Takeuchi, R.J. Geller and N. Fuji, Possible evidence for a double crossing phase transition in D'' beneath Central America from inversion of seismic waveforms, Geophys. Res. Lett., 34, L09314, doi:10.1029/2007GL029642, , 2007.

Takeuchi, N., Morita, Y., Xuyen, N.D. and Zung, N.Q., Extent of the low-velocity region in the lowermost mantle beneath the western Pacific detected by the Vietnamese broadband seismograph array, Geophys. Res. Lett., 35, L05307, doi:10.1029/2008GL033197, , 2008.

Kazama, T., Kawakatsu, H. and Takeuchi, N., Depth-dependent attenuation structure of the inner core inferred from short-period Hi-net data, Phys. Earth Planet. Inter., 167, 155--160, 2008.

Yamada, R., Yamada, I., Shiraishi, H., Tanaka, S., Takagi, Y., Kobayashi, N., Takeuchi, N., Ishihara, Y., Murakami, H., Yomogida, K., Koyama, J., Fujimura, A. and Mizutani, H., Capability of the penetrator seismometer system for lunar seismic observation, Planet. Space Sci., 57, 751--763, 2009.

Takeuchi, N., A low-velocity conduit throughout the mantle in the robust component of a tomography model, Geophys. Res. Lett., 36, L07306, doi:10.1029/2009GL037590, , 2009.

Takeuchi, N., Simulation of heterogeneity sections obtained by neutrino radiography, Earth Planets Space, 62, 2, 215--221, 2010.

Takeuchi, N. and Obara, K., Fine-scale topography of the D" discontinuity and its correlation to volumetric velocity fluctuations, Phys. Earth Planet. Inter., 183, 126--135, 2010.

Iritani, R., N. Takeuchi and H. Kawakatsu, Seismic attenuation structure of the top half of the inner core beneath the northeastern Pacific, Geophys. Res. Lett., 37, L19303, doi:10.1029/2010GL044053, , 2010.

Takeuchi, N., Detection of ridge-like structures in the Pacific Large Low-Shear-Velocity Province, Earth Planet. Sci. Lett., 319-320, 55--64, 2012.

Idehara, K., S. Tanaka and N. Takeuchi, High-velocity anomaly adjacent to the western edge of the Pacific low-velocity province, Geophys. J. Int., 192, 1--6, 2013.

Yamada, R., Garcia, R.F., Lognonne, P., Kobayashi, N., Takeuchi, N., Nebut, T., Shiraishi, H., Calvet, M. and Ganepain-Beyneix, J., On the Possibility of lunar core phase detection using new seismometers for soft-landers in future lunar missions, Planet. Space Sci., 81, 18--31, 2013.

Namiki, A., Sueyoshi, K. and Takeuchi, N., Can a sheet-like low-velocity region form an elongated LIP?, Geochem. Geophys. Geosyst., 8, 3053--3066, 2013.

Iritani, R., Takeuchi, N. & Kawakatsu, H., Intricate heterogeneous structures of the top 300 km of the Earth's inner core inferred from global array data: I. Regional 1D attenuation and velocity profiles, Phys. Earth Planet. Inter., 230, 15--27, 2014.

Iritani, R., Takeuchi, N. & Kawakatsu, H., Intricate heterogeneous structures of the top 300 km of the Earth's inner core inferred from global array data: II. Frequency dependence of inner core attenuation and its implication, Earth Planet. Sci. Lett., 405, 231--243, 2014.

Takeuchi, N., Kawakatsu, H., Tanaka, S., Obayashi, M., Chen,Y.J., Ning, J., Grand, S.P., Niu, F., Ni, J., Iritani, R., Idehara, K. & Tonegawa, T, Upper Mantle Tomography in the Northwestern Pacific Region Using Triplicated P Waves, J. Geophys. Res., 119, 10, 7667--7685, 2014.

Takeuchi, N., Differential Monte Carlo Method for Computing Seismogram Envelopes and Their Partial Derivatives, J. Geophys. Res., 121, 5, 3428--3444, 2016.

Akuhara, T., Mochizuki, K., Kawakatsu, H., & Takeuchi, N., Non-linear waveform analysis for water-layer response and its application to high-frequency receiver function analysis using OBS array, Geophys. J. Int., 206, 1914--1920, 2016.

Wang, D., Takeuchi, N., Kawakatsu, H., & Mori, J., Estimating High Frequency Energy Radiation of Large Earthquakes by Image Deconvolution Back-Projection, Earth Planet. Sci. Lett., 449, 155--163, 2016.

Akuhara, T., Mochizuki, K., Kawakatsu, H. & Takeuchi, N., A fluid-rich layer along the Nankai-trough megathrust fault off the Kii Peninsula inferred from receiver function inversion, J. Geophys. Res., 122, 6524--6537, 2017.

Takeuchi, N., Kawakatsu, H., Shiobara, H., Isse, T., Sugioka, H., Ito, A. & Utada, H, Determination of Intrinsic Attenuation in the Oceanic Lithosphere-Asthenosphere System, Science, 358, 1593--1596, 2017.