2005年
口永良部島火山における人工地震探査--探査の概要と初動の走時について
東京大学地震研究所彙報
- 巻
- 80
- 号
- 1
- 開始ページ
- 11
- 終了ページ
- 40
- 記述言語
- 日本語
- 掲載種別
- 出版者・発行元
- 東京大学地震研究所
Seismic exploration using artificial sources was conducted at Kuchierabujima volcano, southwest Japan in November 2004 by 40 participants from 9 national universities andJapan Meteorological Agency to investigate the subsurface seismic structure. The exploration was the 11th joint experiment under the National Project for Prediction of Volcanic Eruptions. A total of 183 temporal stations equippedwith a 2 Hz vertical component seismometer (including 75 3component seismometers) and a portable data logger were deployed on Kuchierabu Island. Dynamite shots with charges of 10-115 kg were detonated at 19 locations, and seismic signals were successfully recorded. To reveal the P-wave velocity structure, 2955 arrival times of the first motion were picked from the seismograms, and 2187 were classified into ranks A and B. From the record sections and the arrival time data, characteristics reflecting the geological structure were identified. Refracted waves of 5 km/s were observed at stations>5km from the shot points. Apparent velocities near the shot points depend on the surface geology around the shots. P-wave arrived earlier at stations near the summits. Strongly scattered waves were observed similarly near the summits.
- リンク情報
- ID情報
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- ISSN : 0040-8972
- CiNii Articles ID : 110006999818
- CiNii Books ID : AN00162258