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Upper mantle velocity structure in the western Pacific rim estimated from short-period recordings at Matsushiro Seismic Array System
Earth, Planets and Space volume 52, pages459–466(2000)
We investigate lateral variation of the upper mantle P-wave velocity structure in the western Pacific rim using travel times of P phases from regional shallow events. Onsets of direct and later arrivals are manually picked up from short-period waveforms at Matsushiro Seismic Array System in central Japan by consulting the correlation among the waveforms at seven array stations. For the path along Kurile and Alaska seismic zones, observed first arrivals of shallow events (d = 5–50 km) are well explained by a standard travel time table for Japan. Observations provide no strong evidence of a distinct low-velocity zone in the uppermost mantle, and triplicated branches are adequately explained by a slight modification of model 12 by Sugiyama and Nakanishi (1989, 1999). Observed travel times of direct P phases from events along the eastern and western Philippine Sea are slightly larger at around 15° and slightly smaller at around 25°, and the upper mantle is slower and the transition zone and uppermost lower mantle faster in the eastern and western Philippine Sea than in the northwestern Pacific. Such differences could reflect a high temperature in the upper mantle, and accumulation of subducted material at the base of transition zone as a result of the past subduction.
Asano, S., S. Kubota, H. Okada, M. Nogoshi, H. Suzuki, K. Ichikawa, and H. Watanabe, Explosion seismic studies of the underground structure in the Matsushiro Earthquake swarm area, J. Phys. Earth, 17, 77–90, 1969.
Bina, C. R., Mantle discontinuities, Rev. Geophys., 29, 783–793, 1991.
Brudzinski, M. R., W.-P. Chen, R. L. Nowack, and B.-S. Huang, Variation of P wave speeds in the mantle transition zone beneath the northern Philippine Sea, J. Geophys. Res., 102, 11,815–11,827, 1997.
Erdögan, N. and R. L. Nowack, Slant-stack velocity analysis for one-dimensional upper mantle structure using short-period data from MAJO, PureAppl. Geophys., 141, 1–24, 1993.
Fukao, Y., Upper mantle P structure on the ocean side of the Japan-Kurile arc, Geophys. J. R. Astr. Soc., 50, 621–642, 1977.
Fukao, Y., M. Obayashi, H. Inoue, and M. Nenbai, Subducting slabs in the mantle transition zone, J. Geophys. Res., 97, 4809–4822, 1992.
Gaherty, J. B., T. H. Jordan, and L. S. Gee, Depth extent of polarization anisotropy in western Pacific upper mantle, J. Geophys. Res., 101, 22,291–22,309, 1996.
Gaherty, J. B., M. Kato, and T. H. Jordan, Seismological structure of the upper mantle: a regional comparison of seismic layering, Phys. Earth Planet. Int., 110, 21–41, 1999.
Hamada, K, Re-examination of travel time tables for local earthquakes, Pap. Meteorol. Geophys., 35, 109–167, 1984 (in Japanese with English abstract).
Hirth, G. and D. L. Kohlstedt, Water in the oceanic upper mantle: Implication for rheology, melt extraction, and the evolution of the lithosphere, Earth Planet. Sci. Lett., 144, 93–108, 1996.
Inatani, H. and K. Kurita, Upper mantle velocity structure beneath the Ryukyu-Taiwan arc, Zisin, II, 33, 37–49, 1980 (in Japanese with English abstract).
Ita, J. and L. Stixrude, Petrology, elasticity, and composition of the mantle transition zone, J. Geophys. Res., 97, 6849–6866, 1992.
Kanamori, H., Upper mantle structure from apparent velocities of P wave recorded at Wakayama Microearthquake Observatory, Bull. Earthq. Res. Inst., Univ. Tokyo, 45, 657–678, 1967.
Karato, S.-I., Effect of water on seismic wave velocities in the upper mantle, Proc. Japan Academy, 71, Ser. B, 61–66, 1995.
Kato, M. and T. H. Jordan, Seismic structure of the upper mantle beneath the western Philippine Sea, Phys. Earth Planet. Int., 110, 263–283, 1999.
Kato, M., I. Nakanishi, and H. Takayama, Isolation of local site characteristics from teleseismic short-period recordings at Matsushiro Seismic Array System, Bull. Seis. Soc. Am., 2000 (submitted).
Katzman, R., L. Zhao, and T. H. Jordan, High-resolution, two-dimensional vertical tomography of the central Pacific mantle using ScS reverberations and frequency-dependent travel times, J. Geophys. Res., 103, 17,933–17,971, 1998.
Kishimoto, Y., Seismometric investigation of the earth’s interior, Part 3. On the structure of the earth’s mantle (I), Mem. Coll. Sci. Kyoto Univ., Ser. A., 28, 117–142, 1956.
Maki, T., S. Kashiwabara, Y. Osada, M. Nishiwaki, T. Kakishita, and S. Nagare, Determination of apparent velocities and azimuths of distant earthquakes by the Matsushiro Seismic Array System —Effect of dipping structure of the crust and near-surface—, Tech. Rep. Seis. Obs., Japan Meteorol. Agency, 8, 1–21, 1987 (in Japanese with English abstract).
Nagai, A. and S. Kashiwabara, Underground structure under the Matsushiro Seismic Array System, Tech. Rep. Seis. Obs., Japan Meteorol. Agency, 6, 54–60, 1985 (in Japanese with English abstract).
Niazi, M. and D. Anderson, Upper mantle structure of the earth’s upper mantle from apparent velocities ofP waves, J. Geophys. Res., 70, 4622–4640, 1965.
Nolet, G., S. P. Grand, and B. L. N. Kennett, Seismic heterogeneity in the upper mantle, J. Geophys. Res., 99, 23,753–23,766, 1994.
Nowack, R. L., E. Ay, W.-P. Chen, and B.-S. Huang, A seismic profile of the upper mantle along the southwestern edge of the Philippine Sea plate using short-period array data, Geophys. J. Int., 136, 171–179, 1999.
Ohtaki, T. and S. Kaneshima, Continuous high velocity aseismic zone beneath the Izu-Bonin Arc, Geophys. Res. Lett., 21, 1–4, 1994.
Okino, K., M. Ando, S. Kaneshima, and K. Hirahara, The horizontally lying slab, Geophys. Res. Lett., 16, 1059–1062, 1989.
Osada, Y., S. Kashiwabara, A. Nagai, H. Takayama, S. Wakui, I. Morishita, and Y. Tanaka, Matsushiro Seismic Array System (I)—Outline and hypocenter determination of near earthquakes, Tech. Rep. Seis. Obs., Japan Meteorol. Agency, 5, 13–31, 1984 (in Japanese with English abstract).
Ringwood, A. E., Composition and petrology of the Earth’s mantle, 604 pp., McGraw-Hill, New York, 1975.
Sato, H., I. S. Sacks, and T. Murase, The use of laboratory velocity data for estimating temperature and partial melt fraction in the low-velocity zone: Comparison with heat flow and electrical conductivity studies, J. Geophys. Res., 94, 5689–5704, 1989.
Stark, P. B. and R. L. Parker, Velocity bounds from statistical estimates of τ (p) and X(p), J. Geophys. Res., 92, 2713–2719, 1987.
Su, W.-J., R. L. Woodward, and A. M. Dziewonski, Degree 12 model of shear velocity heterogeneity in the mantle, J. Geophys. Res., 99, 6945–6980, 1994.
Suetsugu, D. and I. Nakanishi, Three-dimensional velocity map of the upper mantle beneath the Pacific Ocean as determined from Rayleigh wave dispersion, Phys. Earth Planet. Int., 47, 205–229, 1987.
Sugiyama, T. and I. Nakanishi, Upper mantle P-wave structure of the northwestern rim of the Pacific Ocean, Progr. Abs. Seismo. Soc. Japan, 1, 204, 1989 (in Japanese).
Sugiyama, T. and I. Nakanishi, Upper mantle P-wave structure of the northwestern rim of the Pacific Ocean, Mem. Fac. Sci., Kyoto Univ., Ser. phys. astrophys. geophys. chem, 1999 (submitted).
Tajima, F. and S. P. Grand, Evidence of high velocity anomalies in the transition zone associated with southern Kurile subduction zone, Geophys. Res. Lett., 22, 3139–3142, 1995.
Tajima, F. and S. P. Grand, Variation of transition zone high-velocity anomalies and depression of 660 km discontinuity associated with subduction zones from the southern Kuriles to Izu-Bonin and Ryukyu, J. Geophys. Res., 103, 15,015–15,036, 1998.
Turcotte, D. L. and G. Schubert, Geodynamics: applications of continuum physics to geological problems, 450 pp., John Wiley and Sons, New York, 1982.
van der Hilst, R. D., R. Engdahl, W. Spakman, and G. Nolet, Tomographic imaging of subducted lithosphere below northwest Pacific island arcs, Nature, 353, 37–43, 1991.
van der Hilst, R. D. and T. Seno, Effect of relative plate motion on the deep structure and penetration depth of slabs below the Izu-Bonin and Mariana islands arc, Earth Planet. Sci. Lett., 120, 395–407, 1993.
Walck, M. C., The P-wave upper mantle structure beneath an active spreading centre: The Gulf of California, Geophys. J. R. Astr. Soc., 76, 697–723, 1984.
Walck, M. C., The P-wave upper mantle structure beneath the northwest Pacific rim: A comparison with the Gulf of California. Geophys. J. R. Astr. Soc., 81, 243–276, 1985.
Wessel, P. and W. H. F. Smith, New version of the Generic Mapping Tools released, Eos Trans. AGU, 76, 329, 1995.
Yamazaki, A. and K. Hirahara, The upper-mantle P-wave velocity structure beneath the Northern Japan Arc, as inferred from J-Array data, J. Phys. Earth, 44, 713–728, 1996.
Yamazaki, A., K. Hirahara, and T. Shibutani, Waveform station anomaly —Definition and example for J-Array stations—, J. Phys. Earth, 44, 675–685, 1996.
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Kato, M., Nakanishi, I. Upper mantle velocity structure in the western Pacific rim estimated from short-period recordings at Matsushiro Seismic Array System. Earth Planet Sp 52, 459–466 (2000). https://doi.org/10.1186/BF03351650
- Uppermost Mantle
- Mantle Structure
- Mantle Transition Zone
- Travel Time Curve
- Shallow Event