DEEP-STRUCTURE OF THE NORTHEASTERN JAPAN ARC AND ITS RELATIONSHIP TO SEISMIC AND VOLCANIC ACTIVITY
DEEP-STRUCTURE OF THE NORTHEASTERN JAPAN ARC AND ITS RELATIONSHIP TO SEISMIC AND VOLCANIC ACTIVITY
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DOI：
10.1038/352683a0
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发表时间：
1991-08-22
期刊：
影响因子：
64.8
通讯作者：
HORIUCHI, S
中科院分区：
文献类型：
--
作者：
HASEGAWA, A;ZHAO, DP;HORIUCHI, S
从地震观测中可以获得日本东北部地下可能存在深部岩浆活动的证据。P波速度层析成像反演结果表明，在活火山区的地壳和上地幔中存在低速带。在这些区域内或其周围，在25-40公里深处发现了可能由岩浆活动引起的异常低频微地震;在10-18公里深处发现了与岩浆体上表面相对应的明显的S波反射体。大的地壳地震也发生在低速带周围。这些观测结果揭示了深部岩浆库的分布，并阐明了其与火山弧下浅层地震活动的关系。
Evidence for possible deep-seated magmatic activity beneath northeastern Japan can be obtained from seismic observations. Tomographic inversions of P-wave velocity data show low-velocity zones distributed in the crust and upper mantle beneath active volcanoes. In or around these zones, anomalously low-frequency micro-earthquakes, perhaps caused by magmatic activity, are found at depths of 25-40 km; distinct S-wave reflectors, corresponding to the upper surfaces of magma bodies, are found at depths of 10-18 km. Large crustal earthquakes also occur around the low-velocity zones. These observations reveal the distribution of magma reservoirs at depths and elucidate its relation with shallow seismicity beneath volcanic arcs.