Abstract
The spatiotemporal stress states in the aftershock region of the 2005 West Off Fukuoka Prefecture Earthquake are examined via an analysis of the b values and focal mechanism solutions. The aftershocks are aligned roughly NW–SE, with the southeastern part of the aftershock region believed to correspond to the Kego Fault, which extends beneath the Fukuoka metropolitan area. This study reveals depth-dependent b values in the focal region, where the b values (b = 0.7–1.4) are generally higher above the mainshock depth (9.5 km) and lower (b = 0.5–1.0) at greater depths. The shallower region possesses a significant temporal increase in b values, whereas a lateral b value heterogeneity is observed in the deeper region. The b values (b ~ 1.0) near the mainshock are relatively high, whereas the northwestern and southeastern edges of the deep region have lower b values (b = 0.5–0.7). On the other hand, many of the focal mechanisms for the \(M\ge 3.5\) events are located in the low b value area of the deep region. The stress tensor inversion results reveal a change in stress state from strike-slip to strike-slip/normal faulting. These findings imply that the stress state remains high and/or slightly decreased in the northwestern and southeastern parts of the deep region. These results and the findings of previous research on this earthquake sequence suggest that the likelihood of future large earthquakes along the southeastern part of the aftershock region should be considered relatively high.
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References
Aki, K. (1965). Maximum likelihood estimate of b in the formula logN = a – bM and its confidence limits. Bulletin of Earthquake Research Institute of the University of Tokyo, 43, 237–239.
Asano, K., & Iwata, T. (2006). Source process and near-source ground motions of the 2005 West Off Fukuoka Prefecture Earthquake. Earth, Planets and Space, 58(1), 93–98.
Bott, M. H. P. (1959). The mechanics of oblique slip faulting. Geological. Magazine, 96, 109–117.
Byerlee, J. (1978). Friction of rock. Pure and Applied Geophysics, 116, 615–4626.
Chiba, K. (2019). Spatial and temporal distributions of b values related to long-term slow-slip and low-frequency earthquakes in the Bungo Channel and Hyuga-nada regions, Japan. Tectonphysics, 757, 1–9. https://doi.org/10.1016/j.tecto.2019.02.021
Chiba, K. (2020). Stress state along the western Nankai Trough subduction zone inferred from b values, long-term slow slip events, and low frequency earthquakes. Earth, Planets and Space, 72, 3. https://doi.org/10.1186/s40623-020-1130-7
Dieterich, J. (1994). A constitutive law for rate of earthquake production and its application to earthquake clustering. Journal of Geophysical Research, 99(B2), 2601–2618. https://doi.org/10.1029/93JB02581
El-Isa, Z. H., & Eaton, D. W. (2014). Spatiotemporal variations in the b value of earthquake magnitude-frequency distributions: Classification and causes. Tectonophysics, 615–616, 1–11. https://doi.org/10.1016/j.tecto.2013.12.001
Frohlich, C., & Davis, S. (1993). Teleseismic b values; or, much ado about 1.0. Journal of Geophysical Research, 98(B1), 631–644.
Geospatial Information Authority of Japan. (2006). Crustal deformation and a fault mode of the West-off Fukuoka Prefecture Earthquake in 2005. https://www.gsi.go.jp/common/000025591.pdf(in Japanese).
Gephart, J. W., & Forsyth, D. W. (1984). An improved method for determining the regional stress tensor using earthquake focal mechanism data: Application to the San Fernando earthquake sequence. Journal of Geophysical Research, 89, 9305–9320.
Ghosh, A., Newman, A. V., Thomas, A. M., & Farmer, G. T. (2008). Interface locking along the subduction megathrust from b value mapping near Nicoya Peninsula, Costa Rica. Geophysical Research Letters, 35, L01301. https://doi.org/10.1029/2007GL031617
Gulia, L., & Wiemer, S. (2019). Real-time discrimination of earthquake foreshocks and aftershocks. Nature, 574, 193–199. https://doi.org/10.1038/s41586-019-1606-4
Gutenberg, B., & Richter, C. F. (1944). Frequency of earthquakes in California. Bulletin of the Seismological Society of America, 34, 185–188.
Hardebeck, J. L., & Hauksson, E. (2001). Crustal stress field in southern California and its implications for fault mechanics. Journal of Geophysical Research, 106(B10), 21859–21882.
Hardebeck, J. L., & Michael, A. J. (2006). Damped regional-scale stress inversions: Methodology and examples for southern California and the Coalinga aftershock sequence. Journal of Geophysical Research, 111, B11310. https://doi.org/10.1029/2005JB004144
Horikawa, H. (2006). Rupture process of the 2005 West Off Fukuoka Prefecture, Japan, earthquake. Earth, Planets and Space, 58, 87–92.
Iio, Y., Katao, H., Ueno, T., Enescu, B., Hirano, N., Okada, T., Uchida, N., Matsumoto, S., Matsuhima, T., Uehira, K., & Shimizu, H. (2006). Spatial distribution of seismic stress drops for aftershocks of the 2005 West Off Fukuoka Prefecture Earthquake. Earth, Planets and Space, 58, 1611–1615.
Ishimoto, M., & Iida, K. (1939). Observations sur les seisms enregistré par le microseismograph construit demiement. Bulletin of the Earthquake Research Institute, Tokyo Imperial University, 17, 443–478.
Jaeger, J., & Cook, N. G. W. (1979). Fundamental of Rock Mechanics (3rd ed.). Chapman and Hall.
Martinez-Garzon, P., Kwiatek, G., Ickrath, M., & Bohnhoff, M. (2014). MSATSI: A MATLAB package for stress inversion combining solid classic methodology, a new simplified user-handling and a visualization tool. Seismological Research Letters, 85, 4. https://doi.org/10.1785/0220130189
Matsumoto, S., Uehira, K., Watanabe, A., Goto, K., Iio, Y., Hirata, N., Okada, T., Takahashi, H., Shimizu, H., Shinohara, M., & Kanazawa, T. (2009). High resolution Q-1 estimation based on extension of coda normalization method and its application to P-wave attenuation structure in the aftershock area of the 2005 West Off Fukuoka Prefecture Earthquake (M 7.0). Geophysical Journal International, 179, 1039–1054. https://doi.org/10.1111/j.1365-246X.2009.04313.x
Matsumoto, T., Ito, Y., Matsubayashi, H., & Sekiguchi, S. (2006). Spatial distribution of F-net moment tensors of the 2005 West Off Fukuoka Prefecture Earthquake determined by the extended method of the NIED F-Net routine. Earth Planets Space, 58, 63–67.
Michael, A. J. (1984). Determination of stress from slip data: Faults and folds. Journal of Geophysical Research, 89, 11517–11526.
Michael, A. J. (1987). Stress rotation during the Coalinga aftershock sequence. Journal of Geophysical Research, 92, 7963–7979.
Mogi, K. (1962). Magnitude-Frequency relation for elastic shocks accompanying fractures of various materials and some related problems in earthquakes. Bulletin of the Earthquake Research Institute, University of Tokyo, 40, 831–853.
Nakao, S., Takahashi, H., Matsushima, T., Kohno, Y., & Ichiyanagi, M. (2006). Postseismic deformation following the 2005 West Off Fukuoka Prefecture Earthquake (M7.0) derived by GPS observation. Earth Planets Space, 58, 1617–1620.
Nanjo, K. Z., Ishibe, T., Tsuruoka, D., Schorlemmer, D., Ishigaki, Y., & Hirata, N. (2010). Analysis of the completeness magnitude and seismic network coverage of Japan. Bulletin of the Seismological Society of America, 100(6), 3261–3268. https://doi.org/10.1785/0120100077
Nanjo, K. Z., Izutsu, J., Orihara, Y., Furuse, N., Togo, S., Nitta, H., Okada, T., Tanaka, R., Kamogawa, M., & Nagao, T. (2016). Seismicity prior to the 2016 Kumamoto earthquakes. Earth, Planets and Space, 68, 187. https://doi.org/10.1186/s40623-016-0558-2
Nanjo, K. Z., & Yoshida, A. (2018). A b map implying the first eastern rupture of the Nankai Trough earthquakes. Nature Communications, 9, 1117. https://doi.org/10.1038/s41467-018-03514-3
Nanjo, K. Z., Izutsu, J., Orihara, Y., Kamogawa, Y., & Nagano, T. (2019). Changes in seismicity pattern due to the 2016 Kumamoto Earthquakes identify a highly stressed area on the Hinagu fault zone. Geophysical Research Letters, 46, 16. https://doi.org/10.1029/2019GL083463
National Institute of Advanced Industrial Science and Technology. (2005). Change in future earthquake probability due to fault interaction. https://www.aist.go.jp/Portals/0/resource_images/aist_j/aistinfo/aist_today/vol05_05/vol05_05_p14_15.pdf(in Japanese).
Nishimura, T., Fujiwara, S., Murakami, M., Suito, H., Tobita, M., & Yarai, H. (2006). Fault model of the 2005 Fukuoka-ken Seiho-oki earthquake estimated from coseismic deformation observed by GPS and InSAR. Earth, Planets and Space, 58, 51–56.
Okamura, M., Matsuoka, H., Nakashima, T., Nakata, T., Chida, N., Hirata, K., & Shimazaki, K. (2009). Holocene Paleoseismicity on Kego Fault in Hakata Bay, Northern Kyushu, Japan. Zisin, 2(61), 175–190. (in Japanese).
Scholz, C. H. (1968). The frequency-magnitude relation of microfracturing in rock and its relation to earthquakes. Bulletin of the Seismological Society of America, 58, 399–415.
Scholz, C. H. (2015). On the stress dependence of the earthquake b value. Geophysical Research Letters, 42, 1399–1402. https://doi.org/10.1002/2014GL062863
Schorlemmer, D., Wiemer, S., & Wyss, M. (2004). Earthquake statistics at Parkfield: 1. Stationarity of b values. Journal of Geophysical Research, 109, B12307. https://doi.org/10.1029/2004JB003234
Schorlemmer, D., & Wiemer, S. (2005). Microseismicity data forecast rupture area. Nature, 434, 1086. https://doi.org/10.1038/4341086a
Shimizu, H., Takahashi, T., Okada, T., Kanazawa, T., Iio, Y., Miyamachi, H., Matsushima, T., Ichiyanagi, N., Uchida, N., Iwasaki, T., Katao, H., Goto, K., Matsumoto, S., Hirata, N., Nakao, S., Uehira, K., Shinohara, M., Yakiwara, H., Kame, T., … Hori, M. (2006). Aftershock seismicity and fault structure of the 2005 West Off Fukuoka Prefecture Earthquake (MJMA 7.0) derived from urgent joint observations. Earth, Planets and Space, 58, 1599–1604.
Shimoyama, S., Iso, N., Matsuda, T., Ichihara, T., Chida, N., Okamura, M., Mogi, T., Suzuki, S., Ochiai, H., Nagasawa, S., Imanishi, H., Kawabata, F., Yakabe, H., Ooteki, M., & Matsuura, K. (2005). Trenching study at Yaukuin site across the Kego fault, Fukuoka City, West Japan. Active Fault Research, 25, 117–128.
Smith, W. D. (1981). The b value as an earthquake precursor. Nature, 289, 136–139. https://doi.org/10.1038/289136a0
The Research Group for Active Faults of Japan. (1991). Active Faults in Japan (revised edition) (p. 488). Tokyo: University of Tokyo Press. (in Japanese).
Tormann, T., Enescu, B., Woessener, J., & Wiemer, S. (2015). Randomness of megathrust earthquakes implied by rapid stress recovery after the Japan earthquake. Nature Geoscience, 8(2), 152–158. https://doi.org/10.1038/ngeo2343
Uehira, K., Yamada, T., Shinohara, M., Nakahigashi, K., Miyamachi, H., Iio, Y., Okada, T., Takahashi, H., Matsuwo, N., Uchida, K., Kanazawa, T., & Shimizu, H. (2006). Precise aftershock distribution of the 2005 West Off Fukuoka Prefecture Earthquake (Mj = 7.0) using a dense onshore and offshore seismic network. Earth Planets and Space, 58, 1605–1610.
Urbancic, T. I., Trifu, C. I., Long, J. M., & Young, R. P. (1992). Space-time correlations of b values with stress release. Pure and Applied Geophysics, 139(3), 449–462.
Utsu, T. (1961). A statistical study on the occurrence of aftershocks. Geophysics, 30, 521–605.
Utsu, T. (1992). On seismicity, in Report of Cooperative Research of the Institute of Statistical Mathematics. The Institute of Statistical Mathematics Tokyo, 34, 139–157.
Utsu, T. (1999). Representation and analysis of the earthquake size distribution: A historical review and some approaches. Pure and Applied Geophysics, 155, 509–535.
Wallace, R. E. (1951). Geometry of shearing stress and relationship to faulting. The Journal of Geology, 59, 111–130.
Wang, Z., & Zhao, D. (2006). Seismic evidence for the influence of fluids on the 2005 west off Fukuoka prefecture earthquake in southwest Japan. Physics of the Earth and Planetary Interiors, 155, 313–324.
Warren, N. W., & Latham, G. V. (1970). An experimental study of thermally induced microfracturing and its relation to volcanic seismicity. Journal of Geophysical Research, 75, 4455–4464. https://doi.org/10.1029/JB075i023p04455
Wessel, P., Smith, W. H. F., Scharroo, R. R., Luis, J. F., & Wobbe, F. (2013). Generic mapping tools: Improved version released. Eos Transactions American Geophysical Union, 94, 409–410. https://doi.org/10.1002/2013EO450001
Wiemer, S. (2001). A software package to analyze seismicity: ZMAP. Seismological Research Letters, 72(3), 373–382.
Wiemer, S., & Wyss, M. (2000). Minimum magnitude of completeness in earthquake catalogs: Examples from Alaska, the Western United States, and Japan. Bulletin of the Seismological Society of America, 90, 859–869.
Wiemer, S., McNutt, S. R., & Wyss, M. (1998). Temporal and three-dimensional spatial analyses of the frequency-magnitude distribution near Long Valley Caldera, California. Geophysical Journal International, 134, 409–421. https://doi.org/10.1406/j.1365-246x.1998.00561.x
Woessner, J., & Wiemer, S. (2005). Assessing the quality of earthquake catalogues: Estimating the magnitude of completeness and its uncertainty. Bulletin of the Seismological Society of America, 95(2), 684–498. https://doi.org/10.1785/0120040007
Wyss, M. (1973). Towards a physical understanding of the earthquake frequency distribution. Geophysical Journal of the Royal Astronomical Society, 31, 341–359. https://doi.org/10.1111/j.1365-246X.1973.tb06506.x
Acknowledgements
The author used data from the Japan Meteorological Agency (JMA) unified earthquake catalog (https://www.data.jma.go.jp/svd/eqev/data/bulletin/index.html). The ZMAP MATLAB software package (Wiemer 2001) (http://www.seismo.ethz.ch/static/stat_2010_website/stat-website-pre2010/www.earthquake.ethz.ch/software/zmap.html) was used for the b value analysis. The figures were prepared using the Generic Mapping Tools software package (Wessel et al. 2013). This study was partially funded by Tokio Marine Kagami Memorial Foundation, Japan (EAKF320500). The author thanks the editor Carla Braitenberg and two anonymous reviewers for helping to improve the manuscript.
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Chiba, K. Stress State Inferred from b Value and Focal Mechanism Distributions in the Aftershock Area of the 2005 West Off Fukuoka Prefecture Earthquake. Pure Appl. Geophys. 178, 1165–1179 (2021). https://doi.org/10.1007/s00024-021-02691-5
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DOI: https://doi.org/10.1007/s00024-021-02691-5