小原研究室

主要論文

[2020年]
Baba, S., Takeo, A., Obara, K., Matsuzawa, T., & Maeda, T. Comprehensive detection of very low frequency earthquakes off the Hokkaido and Tohoku Pacific coasts, Northeastern Japan. Journal of Geophysical Research: Solid Earth, 125, e2019JB017988, 2020.
N. Uchida, R. Takagi, Y. Asano, K. Obara, Migration of shallow and deep slow earthquakes toward the locked segment of the Nankai megathrust, Earth Planet. Sci. Lett., 531, https://doi.org/10.1016/j.epsl.2019.1159, 2020.
[2019年]
Kano, M., A. Kato and K. Obara, Episodic tremor and slip silently invades strongly locked megathrust zone at the Nankai Trough subduction, Scientific Reports, 9, 9270, doi:10.1038/s41598-019-45781-0, 2019.
R. Kurihara, K. Obara, A. Takeo, Y. Tanaka, Deep Low‐Frequency Earthquakes Associated With the Eruptions of Shinmoe‐dake in KirishimaVolcanoes, J. Geophys. Res., 124, doi: 10.1029/2019JB018032, 2019.
[2018年]
S.Baba, A.Takeo and K.Obara, A.Kato, T.Maeda, T.Matsuzawa, Temporal activity modulation of deep very low frequency earthquakes in Shikoku, southwest Japan, Geophys. Res. Lett., 45, DOI: 10.1002/2017GL076122, 2018.
N.Poiata, J.P.Vilotte, P.Berbnard, C.Satriano, K.Obara, Imaging different components of a tectonic tremor sequence in southwestern Japan using an automatic statistical detection and location method, Geophys. J. Int., 205, doi:10.1093/gji/ggy070, 1548-1573, 2018.
M. Kano, N. Aso, T. Matsuzawa, S. Ide, S. Annoura, R. Arai, S. Baba, M. Bostock, K. Chao, K. Heki, S. Itaba, Y. Ito, N. Kamaya, T. Maeda, J. Maury, M. Nakamura, T.Nishimura, K. Obana, K. Ohta, N. Poiata, B. Rousset, H. Sugioka, R. Takagi, T.Takahashi, A. Takeo, Y. Tu, N. Uchida, Y. Yamashita, and K. Obara, Development of a Slow Earthquake Database, Seismological Research Letters, doi: 10.1785/0220180021, 2018.
Takagi., R., K. Nishida, T. Maeda, and K. Obara, Ambient seismic noise wavefield in Japan characterized by polarization analysis of Hi-net records, Geophys. J. Int., 215, 3, 1682-1699, doi: 10.1093/gji/ggy334, 2018.
R.Kurihara, K.Obara and A.Takeo, T.Maeda, Migration of deep low frequency tremor triggered by teleseismic earthquakes in the southwest Japan subduction zone, Geophys. Res. Lett., 45, DOI: 10.1002/2017GL076779, 2193-2213, 2018.
T. Wang, J. Zhuang, J. Buckby, K. Obara, H. Tsuruoka, Identifying the recurrence patterns of non‐volcanic tremors using a 2D hidden Markov model with extra zeros, J. Geophys. Res., 123, 10.1029/2017jb015360, 2018.
[2017年]
Toya, M., A. Kato, T. Maeda, K. Obara, T. Takeda and K. Yamaoka, Down-dip variations in a subducting low-velocity zone linked to episodic tremor and slip: a new constraint from ScSp waves, Scientific Reports, 7, 2868, doi:10.1038/s41598-017-03048-6, 2017.
K.Chao, Z.Peng, Y.-J.Hsu, K.Obara, C.Wu, K.-E.Ching, S.van der Lee, H.-C.Pu, P.-L.Leu, and A.Wech, Temporal Variation of Tectonic Tremor Activity in Southern Taiwan Around the 2010 ML6.4 Jiashian Earthquake, J. Geophys. Res., 122, doi:10.1002/2016JB013925, 2017.
[2016年]
K.Chao and K.Obara, Triggered Tectonic Tremor in Various Types of Fault Systems of Japan Following the 2012 Mw8.6 Sumatra Earthquake, J. Geophys. Res., 121, 170-187, doi:10.1002/2015JB012566, 2016.
R. Takagi, K.Obara and T.Maeda, Slow slip event within a gap between tremor and locked zones in the Nankai subduction zone, Geophys. Res. Lett., 43, 1066-1074. doi:10.1002/2015GL066987, 2016.
N. Poiata, C. Satriano,J.P.Vilotte, P.Berbard, and K.Obara, Multi-band array detection and location of seismic sources recorded by dense seismic networks, Geophys. J. Int., 205, 1548-1573, doi:10.1093/gji/ggw071, 2016.
Annoura, S., K. Obara, and T. Maeda, Total energy of deep low-frequency tremor in the Nankai subduction zone, southwest Japan, Geophys. Res. Lett., 43, 2562-2567, doi:10.1002/2016GL06778, 2016.
Takemura, S., T. Maeda, T. Furumura, and K. Obara, Constraining the source location of the 30 May 2015 (Mw 7.9) Bonin deep-focus earthquake using seismogram envelopes of high-frequency P waveforms: occurrence of deep-focus earthquake at the bottom of a subducting slab, Geophys. Res. Lett., 43, 9, 4297-4302, doi:10.1002/2016GL068437, 2016
K. Obara and A. Kato, Connecting slow earthquakes to huge earthquakes, Science, 353, (6296), 253-257. doi:10.1126/science.aaf1512, 2016.
Kato, A., J. Fukuda, S. Nakagawa and K. Obara, Foreshock migration preceding the 2016 Mw 7.0 Kumamoto earthquake, Japan, Geophys. Res. Lett., doi:10.1002/2016GL070079, 2016.
Maeda, T., K. Nishida, R. Takagi, and K. Obara, Reconstruction of a 2D seismic wavefield by seismic gradiometry, Prog. Earth Planet. Sci., 3, 31, doi:10.1186/s40645-016-0107-4, 2016.
J. Gomberg, A. Wech, K. Creager, K. Obara, and D. Agnew, Reconsidering earthquake scaling, Geophys. Res. Lett., 43, 6243-6251, doi:10.1002/2016GL069967, 2016.
T. Wang, J. Zhuang, K. Obara, and H. Tsuruoka, Hidden Markov modelling of sparse time series from non‐volcanic tremor observations, Royal Statistical Society., 66, doi:10.1111/rssc.12194, 691-715, 2016.
[2015年]
Takagi, R., K. Nishida, Y. Aoki, T. Maeda, K. Masuda, M. Takeo, K. Obara, K. Shiomi, M. Sato, and K. Saito, A single bit matters: Coherent noise of seismic data loggers, Seism. Res. Lett., 86, 3, 901-907, doi:10.1785/0220150030, 2015.
Maeda, T., K. Obara, M. Shinohara, T. Kanazawa, K. Uehira, Successive estimation of a tsunami wavefield without earthquake source data: A data assimilation approach toward real-time tsunami forecasting, Geophys. Res. Lett., 42, 7923-7932, doi:10.1002/2015GL065588, 2015.
Sandanbata, O., K. Obara, T. Maeda, R. Takagi, and K. Satake, Sudden changes in the amplitude-frequency distribution of long-period tremors at Aso volcano, southwest Japan, Geophys. Res. Lett., 42, 23, 10256-10262, doi:10.1002/2015GL066443, 2015.
Y.Asano, K.Obara and T. Matsuzawa, H. Hirose, Y. Ito, Possible shallow slow slip events in Hyuga-nada, Nankai subduction zone, inferred from migration of very-low-frequency earthquakes, Geophys. Res. Lett., 42, 331-338, doi:10.1002/2014GL062165, 2015.
Y.Yamashita, H.Yakiwara, Y. Asano, H. Shimizu, K. Uchida, S. Hirano, K. Umakoshi, H. Miyamachi, M. Nakamoto, M. Fukui, M. Kamizono, H. Kanehara, T. Yamada, M. Shinohara, K. Obara, Migrating tremor off southern Kyushu as evidence for slow slip of a shallow subduction interface, Science, 348, 676-679, doi:10.1126/science.aaa4242, 2015.
T. Matsuzawa, Y.Asano and K.Obara, Very low frequency earthquakes off the Pacific coast of Tohoku, Japan, Geophys. Res. Lett., 42, 4318-4325, doi:10.1002/2015GL063959, 2015.
A. A. Delorey, K.Chao and K.Obara, P.A.Johnson, Cascading elastic perturbation in Japan due to the 2012 Mw 8.6 Indian Ocean earthquake, Science Advances, 1, e1500468, doi:10.1126/sciadv.1500468, 2015.
[2014年]
Maeda, T., T. Furumura, and K. Obara, Scattering of teleseismic P-waves by the Japan Trench: A significant effect of reverberation in the seawater column, Earth Planet. Sci. Lett., 397, 1, 101-110, doi:10.1016/j.epsl.2014.04.037, 2014.
Takashi Iidaka, Jun Muto, Kazushige Obara, Toshihiro Igarashi and Bunichiro Shibazaki, Trench-parallel crustal anisotropy along the trench in the fore-arc region of Japan, Geophys. Res. Lett., 41, 6, 1957-1963, doi:10.1002/2013GL058359, 2014.
Aitaro Kato, and Kazushige Obara, Step-like migration of early aftershocks following the 2007 Mw 6.7 Noto-Hanto earthquake, Japan, Geophys. Res. Lett., 41, 3864-3869, doi:10.1002/2014GL060427, 2014.
K.Obara, Contribution of Slow Earthquake Study for Assessing the Occurrence Potential of Megathrust Earthquakes, J. Disaster Research, 9, 317-329, 2014.
A. Kato, T.Igarashi and K. Obara, Detection of a hidden Boso slow slip event immediately after the 2011 Mw 9.0 Tohoku-Oki earthquake, Geophys. Res. Lett., doi:10.1002/2014GL061053, 2014.
J. Han, J. Vidale, H. Houston, K. Chao, K. Obara, Triggering of tremor and inferred slow slip by small earthquakes at the Nankai subduction zone in southwest Japan, Geophys. Res. Lett., 41, doi:10.1002/2014GL061898, 2014.
J. Fukuda, A. Kato, K. Obara, S. Miura, T. Kato, Imaging of the early acceleration phase of the 2013-2014 Boso slow slip event, Geophys. Res. Lett., 41, doi:10.1002/2014GL061550, 2014.
[2013年]
Kato, A., T. Igarashi, K. Obara, S. Sakai, T. Takeda, A. Saiga, T. Iidaka, T. Iwasaki, N. Hirata, K. Goto, H. Miyamachi, T. Matsushima, A. Kubo, H. Katao, Y. Yamanaka, T. Terakawa, H. Nakamichi, T. Okuda, S. Horikawa, N. Tsumura, N. Umino, T. Okada, M. Kosuga, H. Takahashi and T. Yamada, Imaging the source regions of normal faulting sequences induced by the 2011 M9.0 Tohoku-Oki earthquake, Geophys. Res. Lett., 40, doi:10.1002/grl.50104, 2013.
Kato, A., J. Fukuda, and K. Obara, Response of seismicity to static and dynamic stress changes induced by the 2011 M9.0 Tohoku-Oki earthquake, Geophys. Res. Lett., 40, doi:10.1002/grl.50699, 2013.
Takashi Iidaka and Kazushige Obara, Shear-wave splitting in a region with newly-activated seismicity after the 2011 Tohoku earthquake, Earth Planets Space, 65, 1059-1064, doi:10.5047/eps.2013.02.003, 2013.
T. Nishimura, T.Matsuzawa and K.Obara, Detection of short-term slow slip events along the Nankai Trough, southwest Japan, using GNSS data, J. Geophys. Res., 118, 3112-3125, doi:10.1002/jgrb.50222, 2013.
T.Matsuzawa, B.Shibazaki and K. Obara, H. Hirose, Comprehensive model of short- and long-term slow slip events in the Shikoku region of Japan, incorporating a realistic plate configuration, Geophys. Res. Lett., 40, 5125-5130, doi:10.1002/grl.51006, 2013.
R. Ishida, Y. Hiramatsu and T. Matsuzawa, K. Obara, Average slip rate at the transition zone on the plate interface beneath the Kii Peninsula, Japan, estimated from deep low-frequency tremors, Earth Planets Space, 65, 1047-1051, doi:10.5047/eps.2013.04.003, 2013.
K. Chao, Z.Peng, H. Gonzalez-Huizar, C. Aiken, B. Enescu, H. Kao, A. Wech, A. Velasco, K. Obara, and T. Matsuzawa, A Global Search for Triggered Tremor Following the 2011 Mw 9.0 Tohoku Earthquake, Bull. Seism. Soc. Am., 103, 1551-1571, doi:10.1785/0120120171, 2013.
[2013年]
T. Nishimura, T. Matsuzawa and K.Obara, 2013, Detection of short-term slow slip events along the Nankai Trough, southwest Japan, using GNSS data, Journal of Geophysical Research,DOI: 10.1002/jgrb.50222.
[2012年]
K.Obara, 2012, New detection of tremor triggered in Hokkaido, northern Japan by the 2004 Sumatra-Andaman earthquake, Geophysical Research Letters,doi:10.1029/2012GL053339.
K.Obara, T.Matsuzawa and S.Tanaka, T.Maeda, 2012, Depth-dependent mode of tremor migration beneath Kii Peninsula, Nankai subduction zone , GeophysicalResearch Letters, 39, L10308,doi:10.1029/2012GL051420.
A.Kato, K.Obara, T. Igarashi, H. Tsuruoka, S. Nakagawa and N. Hirata , 2012, Propagation of Slow Slip Leading Up to the 2011Mw 9.0 Tohoku-Oki Earthquake ,Science , 335, 705-708.
Shibazaki, B., K. Obara, T. Matsuzawa and H. Hirose, Modeling of slow slip events along the deep subduction zone in the Kii Peninsula and Tokai regions, southwest Japan, J. Geophys. Res., 117, B06311, doi:10.1029/2011JB009083, 2012.
[2011年]
K.Obara, T.Matsuzawa, S.Tanaka, T.Kimura, and T.Maeda, Migration properties of non‐volcanic tremor in Shikoku, southwest Japan, Geophys. Res. Lett., 38, L09311, doi:10.1029/2011GL047110, , 2011
K.Obara, Characteristics and interactions between non-volcanic tremor and related slow earthquakes in the Nankai subduction zone, southwest Japan, J. Geodynamics, 52, 229--248, 2011.
T. Maeda, K. Obara, T. Furumura, and T. Saito, Interference of long‐period seismic wavefield observed by the dense Hi‐net array in Japan, J. Geophys. Res., 116, B10303, doi:10.1029/2011JB008464, 2011.
[2010年]
Obara, K., Phenomenology of deep slow earthquake family in southwest Japan: Spatiotemporal characteristics and segmentation, J. Geophys. Res., 115, B00A25, doi:10.1029/2008JB006048, , 2010.
Obara, K. and M. Matsumura, Reverse Propagation of Surface Waves Reflected from a Sea Mountain range in the northwestern Pacific, Bull. Seism. Soc. Am., 100, 1342--1349, 2010.
Obara, K., T. Maeda, S. Tanaka and T. Matsuzawa, Depth-dependent activity of non-volcanic tremor in southwest Japan, Geophys. Res. Lett., 37, L13306, doi:10.1029/2010GL043679, , 2010.
Aoi, S., B. Enescu, W.Suzuki, Y. Asano, K. Obara, T. Kunugi and K. Shiomi, Stress transfer in the Tokai subduction zone from the 2009 Suruga Bay earthquake in Japan, Nature Geoscience, 3, 496--500, 2010.
Hirose, H. and K. Obara, Recurrence behavior of short-term slow slip and correlated non-volcanic tremor episodes in western Shikoku, southwest Japan, J. Geophys. Res., 115, B00A21, doi:10.1029/2008JB006050, , 2010.
Sekine, S., H. Hirose and K. Obara, Along-strike variations in short-term slow slip events in the southwest Japan subduction zone, J. Geophys. Res., 115, B00A27, doi:10.1029/2008JB006059, , 2010.
Ueno, T., T. Maeda, K. Obara, Y. Asano and T. Takeda, Migration of low frequency tremor revealed from multiple array analyses in western Shikoku, Japan, J. Geophys. Res., 115, B00A26, doi:10.1029/2008JB006051, , 2010.
Kimura, H., T. Takeda, K. Obara and K. Kasahara, Seismic Evidence for Active Underplating Below the Megathrust Earthquake Zone in Japan, Science, 329, 210--212, 2010.
Hirose, H., Y. Asano, K. Obara, T. Kimura, T. Matsuzawa, S. Tanaka and T. Maeda , Slow Earthquakes Linked Along Dip in the Nankai Subduction Zone, Science, 330, 1502, , 2010.
Hirose, T., Y. Hiramatsu and K. Obara, Characteristics of short-term slow slip events estimated from deep low-frequency tremors in Shikoku, Japan, J. Geophys. Res., 115, B10304, doi:10.1029/2010JB007608, 2010.
Matsuzawa, T., H. Hirose, B. Shibazaki and K. Obara, Modeling short- and long-term slow slip events in the seismic cycles of large subduction earthquakes, J. Geophys. Res., 115, B12301, doi:10.1029/2010JB007566, 2010.
[2009年]
Obara, K. and T. Maeda, Reverse propagation of T waves from the Emperor seamount chain, Geophys. Res. Lett., 36, L08304, doi:10.1029/2009GL037454, , 2009.
Obara, K., Inhomogeneous distribution of deep slow earthquake activity along the strike of the subducting Philippine Sea Plate, Gondwana Research, 16, 512--526, 2009.
Obara, K. and S. Sekine, Characteristic activity and migration of episodic tremor and slow-slip events in central Japan, Earth Planets Space, 61, 853--862, 2009.
Maeda, T. and K. Obara, Spatiotemporal distribution of seismic energy radiation from low-frequency tremor in western Shikoku, Japan, J. Geophys. Res., 114, B00A09, doi:10.1029/2008JB006043, , 2009.
Ito, Y., K. Obara, T. Matsuzawa and T. Maeda, Very low frequency earthquakes related to small asperities on the plate boundary interface at the locked to aseismic transition, J. Geophys. Res., 114, B00A13, doi:10.1029/2008JB006036, , 2009.
Matsuzawa, T., K. Obara and T. Maeda, Source duration of deep very low frequency earthquakes in western Shikoku, Japan, J. Geophys. Res., 114, B00A11, doi:10.1029/2008JB006044, , 2009.
小原一成, フィリピン海プレート沈み込みに伴う西南日本のスロー地震群の発見, 地震2, 61, S315--S327, 2009.
小原一成, 短期的スロースリップ・深部低周波微動、地震予知連絡会編「地震予知連絡会40年のあゆみ」, 国土地理院, 2009.
小原一成, 独立行政法人防災科学技術研究所、地震予知連絡会編「地震予知連絡会40年のあゆみ」, 国土地理院, 2009.
 
このページのトップへ