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Detailed seismic attenuation structure beneath Hokkaido, northeastern Japan: Arc-arc collision process, arc magmatism, and seismotectonics
https://nied-repo.bosai.go.jp/records/4013
https://nied-repo.bosai.go.jp/records/401317898ae2-ee05-4033-aedb-a03624d3c5aa
| Item type | researchmap(1) | |||||||||||||||||||
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| 公開日 | 2023-03-30 | |||||||||||||||||||
| タイトル | ||||||||||||||||||||
| 言語 | en | |||||||||||||||||||
| タイトル | Detailed seismic attenuation structure beneath Hokkaido, northeastern Japan: Arc-arc collision process, arc magmatism, and seismotectonics | |||||||||||||||||||
| 言語 | ||||||||||||||||||||
| 言語 | eng | |||||||||||||||||||
| 著者 |
Saeko Kita
× Saeko Kita
× Junichi Nakajima
× Akira Hasegawa
× Tomomi Okada
× Kei Katsumata
× Youichi Asano
× Takeshi Kimura
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| 抄録 | ||||||||||||||||||||
| 内容記述タイプ | Other | |||||||||||||||||||
| 内容記述 | In this study, we imaged a detailed seismic attenuation structure (frequency-independent Q(-1)) beneath Hokkaido, Japan, by merging waveform data from a dense permanent seismic network with those from a very dense temporary network. Corner frequency of each event used for t* estimation was determined by the S coda wave spectral ratio method. The seismic attenuation (Q(p)(-1)) structure is clearly imaged at depths down to about 120 km. For the fore-arc side of Hokkaido, high-Q(p) zones are imaged at depths of 10 to 80 km in the crust and mantle wedge above the Pacific slab. Low-Q(p) zones are clearly imaged in the mantle wedge beneath the back-arc areas of eastern and southern Hokkaido. These low-Q(p) zones, extending from deeper regions, extend to the Moho beneath volcanoes, the locations of which are consistent with those of seismic low-velocity regions. These results suggest that the mantle wedge upwelling flow occurs beneath Hokkaido, except in the area where there is a gap in the volcano chain. In contrast, an inhomogeneous seismic attenuation structure is clearly imaged beneath the Hokkaido corner. A broad low-Q(p) zone is located at depths of 0-60 km to the west of the Hidaka main thrust. The location almost corresponds to that of the seismic low-velocity zone in the collision zone. The fault planes of the 1970 M6.7 and 1982 M7.1 earthquakes are located at the edges of this broad low-Q(p) zone. Observations in this study indicate that our findings contribute to understanding the detailed arc-arc collision process, magmatism, and seismotectonics beneath Hokkaido. | |||||||||||||||||||
| 言語 | en | |||||||||||||||||||
| 書誌情報 |
en : JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 巻 119, 号 8, p. 6486-6511 |
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| 出版者 | ||||||||||||||||||||
| 言語 | en | |||||||||||||||||||
| 出版者 | AMER GEOPHYSICAL UNION | |||||||||||||||||||
| ISSN | ||||||||||||||||||||
| 収録物識別子タイプ | EISSN | |||||||||||||||||||
| 収録物識別子 | 2169-9356 | |||||||||||||||||||
| DOI | ||||||||||||||||||||
| 関連識別子 | 10.1002/2014JB011099 | |||||||||||||||||||
