Abstract
We explored crustal deformation associated with the foreshocks and the main shock of the 2016 Kumamoto earthquake sequence. We conducted kinematic-Global Navigation Satellite System analysis for the foreshocks, and succeeded in separately retrieving the coseismic crustal deformation for the two M6-class events that occurred nearly contemporaneously (within 3 h). Our fault model shows that the first seismic event occurred in the northern part of the Takano-Shirahata segment of the Hinagu Fault, while the second occurred in the southern part of the segment. For the main shock, we mapped the widely distributed ground displacements in and around the Futagawa Fault zone by conducting an Interferometric Synthetic Aperture Radar analysis. The obtained displacement field shows clear displacement boundaries linearly along the Futagawa and the Hinagu faults, across which the sign of the displacement component turns to the opposite, suggesting that the two faults were intimately involved with the main shock. The previously known fault trace of the Futagawa Fault terminates at the western edge of the Aso Caldera, but the intense deformation implying fault ruptures clearly appears within the caldera. Our fault model suggests that the main rupture occurred on the Futagawa Fault in a right-lateral fashion with normal faulting. The rupture on the Futagawa Fault extends into the Aso Caldera, and the fault plane dips oppositely toward the southeast, suggesting that the rupture propagates eastward on a conjugate fault against the main fault. The rupture on the Hinagu Fault shows a right-lateral fault motion on a plane dipping west.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Cervelli P, Murray MH, Segall P, Aoki Y, Kato T (2001) Estimating source parameters from deformation data, with an application to the March 1997 earthquake swarm off the Izu Peninsula, Japan. J Geophys Res 106:11217–11237
Efron B (1979) Bootstrap methods: another look at the jackknife. Ann Statis 7:1–26
Headquarters for Earthquake Research Promotion (2013) Evaluation of active faults to date. http://jishin.go.jp/main/chousa/katsudansou_pdf/93_futagawa_hinagu_2.pdf. Accessed 8 Oct 2017 (in Japanese)
Japan Meteorological Agency (2016) CMT catalog. http://www.data.jma.go.jp/svd/eqev/data/mech/cmt/fig/cmt20160416012505.html. Accessed 10 Oct 2017. (in Japanese)
Jónsson S, Zebker H, Segall P, Amelung F (2002) Fault slip distribution of the 1999 Mw 7.1 Hector mine, California, earthquake, estimated from satellite radar and GNSS measurements. Bull Seismol Soc Am 92:1377–1389
Kawamoto S, Hiyama Y, Ohta Y, Nishimura T (2016) First result from the GEONET real-time analysis system (REGARD): the case of the 2016 Kumamoto earthquakes. Earth Planets Space 68:190. https://doi.org/10.1186/s40623-016-0564-4
Kobayashi T (2017) Earthquake rupture properties of the 2016 Kumamotot earthquake foreshocks (Mj6.5 and Mj6.4) revealed by conventional and multiple-aperture InSAR. Earth Planets Space 69:7. https://doi.org/10.1186/s40623-016-0594-y
Matsuda T (1975) Magnitude and recurrence interval of earthquakes from a fault. J Seismol Soc Jpn, 2 28:269–283 (in Japanese with English abstract)
Metropolis N, Rosenbluth A, Rosenbluth M, Teller A, Teller E (1953) Equation of state calculations by fast computing machines. J Chem Phys 21:1087–1092
Nakagawa H, Toyofuku T, Kotani K, Miyahara B, Iwashita C, Kawamoto S, Hatanaka Y, Munekane H, Ishimoto M, Yutsudo T, Ishikura N, Sugawara Y (2009) Development and validation of GEONET new analysis strategy (Version 4). J Geogr Surv Inst 118:1–8 (in Japanese)
Okada Y (1985) Surface deformation due to shear and tensile faults in a halfspace. Bull Seismol Soc Am 75:1135–1154
Wessel P, Smith WH (1998) New, improved version of generic mapping tools released. Eos Trans AGU 79:579
Acknowledgements
ALOS-2 data were provided by the Earthquake Working Group under a cooperative research contract with the Japan Aerospace Exploration Agency (JAXA). ALOS-2 data are owned by JAXA. Generic Mapping Tools (GMT) provided by Wessel and Smith (1998) were used to construct the figures. Hypocenter data processed by the Japan Meteorological Agency (JMA) were used. Part of the GNSS data was provided by the JMA. We thank the editor and two anonymous reviewers for their constructive comments.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 Springer International Publishing AG, part of Springer Nature
About this paper
Cite this paper
Kobayashi, T., Yarai, H., Kawamoto, S., Morishita, Y., Fujiwara, S., Hiyama, Y. (2018). Crustal Deformation and Fault Models of the 2016 Kumamoto Earthquake Sequence: Foreshocks and Main Shock. In: Freymueller, J., Sánchez, L. (eds) International Symposium on Advancing Geodesy in a Changing World. International Association of Geodesy Symposia, vol 149. Springer, Cham. https://doi.org/10.1007/1345_2018_37
Download citation
DOI: https://doi.org/10.1007/1345_2018_37
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-12914-9
Online ISBN: 978-3-030-12915-6
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)