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Magnetic constraints on the subsurface structure of Akita-Yakeyama volcano, northeast Japan
Earth, Planets and Space volume 50, pages 153–163 (1998)
Abstract
Magnetic analyses have been conducted in and around Akita-Yakeyama volcano at the northwestern edge of the Sengan Geothermal Area, northeast Japan to reveal the regional and local subsurface structures of the area. First, a magnetization intensity mapping method has been applied to analyze aeromagnetic anomalies of the area. Generally, magnetization highs and lows lie on volcanic rocks which are normally and reversely magnetized, respectively. Magnetization lows with small amplitudes are distributed on hydrothermally altered areas. These results imply the usefulness of the method to estimate the young volcanic activities of Quaternary volcanic areas. Detailed magnetic modeling reveals the subsurface structure of Akita-Yakeyama volcano itself. Rock magnetic data from volcanic rocks, both from the surface and cores in the geothermal exploration wells, have been employed for the modeling. The resultant magnetic structure indicates the following: the surface volcanic rocks are underlain by granitic intrusions which have minimum thicknesses of about 2,000 m below the northern flank of volcano; in the southern flank, the surface volcanic rocks are underlain widely by the Old-Tamagawa Welded Tuffs which are reversely magnetized. These results show a good agreement with a geologic interpretation in and around the volcano, especially with a hypothesis of the existence of buried calderas below the present volcano.
References
Bhattacharyya, B. K., Magnetic anomalies due to prism-shaped bodies with arbitrary polarization, Geophysics, 29, 517–531, 1964.
Blakely, R. J., Potential Theory in Gravity and Magnetic Applications, 441 pp., Cambridge Univ. Press, New York, 1995.
Blakely, R. J. and V. J. Grauch, Magnetic models of crystalline terrane: Accounting for the effect of topography, Geophysics, 48, 1551–1557, 1983.
Komazawa, M., Gravimetric analysis of the Sengan geothermal area, northeast Japan, Rept. Geol. Surv. Japan, 266, 399–424, 1987 (in Japanese with English abstract).
Ministry of International Trade and Industry (MITI), Compilation of aeromagnetic anomaly maps, Report on R & D of the Regional Geothermal Exploration Study, 1978.
Nakatsuka, T., Minimum norm inversion of magnetic anomalies with application to aeromagnetic data in the Tanna area, central Japan, J. Geomag. Geoelectr., 47, 295–311, 1995.
New Energy and Industrial Technology Development Organization (NEDO), Abstract of the Report on the 1,500 m-deep Drill Hole (N59-SN-5) in the Sengan Geothermal Area, 101 pp., 1986a (in Japanese).
New Energy and Industrial Technology Development Organization (NEDO), Abstract of the Report on the 1,500 m-deep Drill Hole (N59-SN-6K) in the Sengan Geothermal Area, 107 pp., 1986b (in Japanese). New Energy and Industrial Technology Development Organization (NEDO), Abstract of the Report on the 3,000 m-deep Drill Hole in the Sengan Geothermal Area, 187 pp., 1988 (in Japanese).
Nish, Y., T. Mimura, A. Abe, S. Takagi, S. Tamanyu, and T. Noda, N61-SN-7DWell surveys of the “Confirmation Study of the Effectiveness of Prospecting Techniques for Deep Geothermal Resources” in Sengan geothermal area, Geothermal Energy, 14, 2–26, 1989 (in Japanese).
Okubo, Y., H. Tsu, and K. Ogawa, Estimation of Curie point temperature and geothermal structure of island arcs of Japan, Tectonophysics, 159, 279–290, 1989.
Okuma, S. and S. Suto, Recompiled aeromagnetic anomaly maps of the Sengan Geothermal Area on a scale of 1:100,000, four maps, Open-file Rept. Geol. Surv. Japan, 24, 1986.
Okuma, S. and S. Suto, Magnetic structure of the Sengan geothermal area, Rept. Geol. Surv. Japan, 266, 425–447, 1987 (in Japanese with English abstract).
Okuma, S., M. Makino, and T. Nakatsuka, Magnetization intensity mapping in and around Izu-Oshima volcano, Japan, J. Geomag. Geoelectr., 46, 541–556, 1994a.
Okuma, S., A. McCafferty, and W. D. Stanley, Magnetization intensity mapping in Yellowstone national park, EOS, 75, 200, 1994b.
Research group for the geological map of Sengan Geothermal Area, Explanatory text of the geological map of Sengan Geothermal Area, scale 1:100,000, Geol. Surv. Japan, 1985 (in Japanese with English abstract, 1 p.).
Suto, S., Volcanic activity during Pliocene to Pleistocene in southern part of the Sengan (Hachimantai) geothermal area, northeast Japan-Paleomagnetic study and age determination of andesite volcanoes, Bull. Geol. Surv. Japan, 36, 513–533, 1985 (in Japanese with English abstract).
Suto, S., Large scale felsic pyroclastic flow deposits in the Sengan geothermal area, northeast Japan—Tamagawa and Old-Tamagawa Welded Tuffs, Rept. Geol. Surv. Japan, 266, 77–142, 1987 (in Japanese with English abstract).
Suto, S., Explanatory text of the geological map of the central part of the Sengan Geothermal Area, scale 1:50,000, Geol. Surv. Japan, 1992 (in Japanese with English abstract, 6 p.).
Suto, S. and S. Mukoyama, Volcanic history at northern part of the Sengan geothermal area, northeast Japan, on the basis of paleomagnetic study, Rept. Geol. Surv. Japan, 266, 143–158, 1987 (in Japanese with English abstract).
Talwani, M., Computation with the help of a digital computer of magnetic anomalies caused by bodies of arbitrary shape, Geophysics, 30, 797–817, 1965.
Uchida, T. and Y. Mitsuhata, Two-dimensional inversion and interpretation of magnetotelluric data in the Sumikawa geothermal field, Japan, Rept. Geol. Surv., 282, 17–49, 1995.
White, D. E., Some principles of Geyser activity, mainly from Steam boat spring, Nevada, Am. Jour. Sci., 265, 641–684, 1967.
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Okuma, S. Magnetic constraints on the subsurface structure of Akita-Yakeyama volcano, northeast Japan. Earth Planet Sp 50, 153–163 (1998). https://doi.org/10.1186/BF03352096
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DOI: https://doi.org/10.1186/BF03352096