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Imaging the high b-value anomalies within the subducting Pacific plate in the Hokkaido corner
Earth, Planets and Space volume 58, pagese49–e52(2006)
The frequency-magnitude distribution (b-value) for seismicity within the Pacific plate is not definitely homogeneous. An anomaly of b-value higher than 0.9 is detected within the descending Pacific plate in the Hokkaido corner. In the western Hokkaido, the anomaly exists at a depth of about 150 km, which is directly beneath active volcanoes. In the eastern Hokkaido, the anomalies exist at approximately 200 and 300 km depths, which is tens of kilometers sideways from active volcanoes. The results obtained in this paper are more reliable than previous studies on b-value heterogeneity within descending plates, since I used a catalog homogeneous, both in time and space, which was obtained through re-examination of all seismograms and relocation of hypocentral parameters based on arrival times from fixed seismic stations.
Bayrak, Y. and S. Ozturk, Spatial and temporal variation of the aftershock sequence of the 1999 Izmit and Duzce earthquakes, Earth Planets Space, 56, 933–944, 2004.
Bender, B., Maximum likelihood estimation of b-values for magnitude grouped data, Bull. Seismol. Soc. Am., 73, 831–851, 1983.
Frohlich, C. and S. Davis, Teleseismic b-values: or, much ado about 1.0, J. Geophys. Res., 98, 631–644, 1993.
Gutenberg, R. and C. F. Richter, Frequency of earthquakes in California, Bull. Seismol. Soc. Am., 34, 185–188, 1944.
Habermann, R. E., Man-made change of seismicity rates, Bull. Seismol. Soc. Am., 77, 141–159, 1987.
Hamilton, T. and J. McCloskey, Breakdown in power-law scaling in an analogue model of earthquake rupture and stick-slip, Geophys. Res. Lett., 24, 465–468, 1997.
Huang, Q., Search for reliable precursors: A case study of the seismic quiescence of the 2000 western Tottori prefecture earthquake, J. Geophys. Res., 111, B04301, doi:10.1029/2005JB003982, 2006.
Ikeya, M. and Q. Huang, Earthquake frequency and moment magnitude relations for mainshocks, foresohocks and aftershocks: Theoretical b-values, Episodes, 20, 181–184, 1997.
Ishimoto, M. and K. Iida, Observations of earthquakes registered with the microseimograph constructed recently, Bull. Earthquake Res. Inst. Univ Tokyo, 17, 443–478, 1939.
Katsumata, K. and M. Kasahara, Making a temporally homogeneous seismic catalog, Geophysical Bulletin of Hokkaido Univ., 67, 213–224, 2004 (in Japanese).
Katsumata, K., N. Wada, and M. Kasahara, Newly imaged shape of the deep seismic zone within the subducting Pacific plate beneath the Hokkaido corner, Japan-Kurile arc-arc junction, J. Geophys. Res., 108(B12), 2565, doi:10.1029/2002JB002175, 2003.
Mogi, K., Magnitude-frequency relation for elastic shocks accompanying fractures of various materials and some related problems in earthquakes, Bull. Earthquake Res. Inst., Univ. Tokyo, 40, 831–853, 1962.
Murase, K., A characteristic change in fractal dimension prior to the 2003 Tokachi-oki earthquake (MJ = 8.0), Hokkaido, northern Japan, Earth Planets Space, 56, 401–405, 2004.
Nakajima, J., T. Matsuzawa, A. Hasegawa, and D. Zhao, Three dimensional structures of Vp, Vs, and Vp/Vs beneath the northeastern Japan arc: implications for arc magmatism and fluids, J. Geophys. Res., 106, 21843–21857, 2001.
Nakaya, S., Spatiotemporal variation in b-value within the subducting slab prior to the 2003 Tokachi-oki earthquake (M 8.0), Japan, J. Geophys. Res., 111, B03311, doi:10.1029/2005JB003658, 2006.
Pacheco, J. F., C. H. Scholz, and L. R. Sykes, Changes in frequency-size relationship from small to large earthquakes, Nature, 355, 71–73, 1992.
Reasenberg, P. A., Second-order moment of Central California seismicity, 1969–1982, J. Geophys. Res., 90, 5479–5495, 1985.
Scholz, C. H., The magnitude-frequency relation of microfracturing in rock and its relation to earthquake, Bull. Seismol. Soc. Am., 58, 399–415, 1968.
Schorlemmer, D., S. Wiemer, and M. Wyss, Variation in earthquake-size distribution across different stress regimes, Nature, 437, 539–542, 2005.
Urbanic, T. I., C. I. Trifu, J. M. Long, and R. P. Toung, Space-time correlations of b-values with stress release, Pure Appl. Geophys., 139, 449–462, 1992.
Warren, N. W. and G. V. Latham, An experimental study of thermally induced microfracturing and its relation to volcanic seismicity, J. Geo-phys. Res., 75, 4455–4464, 1970.
Wessel, P. and W. H. F. Smith, Free software helps map and display data, EOS Trans. Amer. Geophys. U., 72, 441, 445–446, 1991.
Wiemer, S. and J. P. Benoit, Mapping the b-value anomaly at 100 km depth in the Alaska and New Zealand subduction zones, Geophys. Res. Lett., 23, 1557–1560, 1996.
Wiemer, S. and K. Katsumata, Spatial variability of seismicity parameters in aftershock zones, J. Geophys. Res., 104, 13135–13151, 1999.
Wiemer, S. and M. Wyss, Mapping the frequency-magnitude distribution in asperities: An improved technique to calculate recurrence times?, J. Geophys. Res., 102, 15115–15128, 1997.
Wyss, M., Towards a physical understanding of the earthquake frequency distribution, Geophys. J. R. Astron. Soc., 31, 341–359, 1973.
Wyss, M., A. Hasegawa, and J. Nakajima, Source and path of magma for volcanoes in the subduction zone of northeastern Japan, Geophys. Res. Lett., 28, 1819–1822, 2001.
Zhao, D., A. Hasegawa, and S. Horiuchi, Tomographic imaging of P and S wave velocity structure beneath northeastern Japan, J. Geophys. Res., 97, 19909–19928, 1992.
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Katsumata, K. Imaging the high b-value anomalies within the subducting Pacific plate in the Hokkaido corner. Earth Planet Sp 58, e49–e52 (2006) doi:10.1186/BF03352640
- Pacific plate
- deep seismic zone