Source image of low-frequency events in Nankai trough

南开海槽低频事件源图

• 批准号: 20740262
• 负责人: OBANA Koichiro
• 金额: $ 2.5万
• 依托单位: Japan Agency for Marine-Earth Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2008
• 资助国家: 日本
• 起止时间: 2008 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20740262/
• 关键词: 南海トラフ; 低周波微動; 海底地震計; 付加体; 分岐断層

Anomalous very-low-frequency (VLF) earthquakes have been observed near the trough axis along the Nankai trough by land seismic networks. The VLF earthquakes were characterized by a dominant frequency of about 10 s and a lack of energy at higher frequencies. This study shows that VLF earthquakes and low frequency tremors occurred near the toe of the accretionary prism based on close range observations using ocean bottom seismographs deployed in the source area. The VLF earthquakes have a focal mechanism of a low-angle reverse fault. The low-frequency events likely relate to an activity of reverse fault in a shallow accretionary prism.

陆地地震台网在南海海槽沿着槽轴附近观测到异常甚低频地震。VLF地震的特征是主频率约为10 s，在更高的频率上缺乏能量。这项研究表明，甚低频地震和低频震颤发生在近距离观测的基础上，使用海底地震仪部署在震源区的脚的增生棱镜。VLF地震的震源机制为低角度逆断层。低频事件可能与浅增生棱柱体中逆断层活动有关。

项目成果

広帯域海底地震計によって観測された紀伊半島沖の超低周波地震活動

宽带海底地震仪观测到纪伊半岛沿岸的甚低频地震活动

• 发表时间: 2010
• 作者: Obana;K.;Manabu Morishige;Koichiro Obana;尾鼻浩一郎
• 通讯作者: 尾鼻浩一郎

南海トラフ付加体先端付近で発生する低周波地震の震源像の解明に向けたOBS自然地震観測

OBS天然地震观测旨在阐明南海海槽增生棱柱尖端附近发生的低频地震的震中图像

• 发表时间: 2009
• 作者: Masaki Yoshida ;Tomoeki Nakakuki.;尾鼻浩一郎;Masaki Yoshida;尾鼻浩一郎
• 通讯作者: 尾鼻浩一郎

Low-frequency tremors associated with reverse faults in a shallow accretionary prism

• DOI: 10.1016/j.epsl.2009.08.005
• 发表时间: 2009-09-30
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Obana, Koichiro;Kodaira, Shuichi
• 通讯作者: Kodaira, Shuichi

Shallow Very-Low-Frequency Earthquakes off the Kii Peninsula Observed by Broadband Ocean Bottom Seismographs American Geophysical Union.

美国地球物理联盟宽带海底地震仪观测到的纪伊半岛浅层甚低频地震。

• 发表时间: 2010
• 作者: Obana;K.
• 通讯作者: K.

Shallow Very-Low-Frequency Earthquakes off the Kii Peninsula Observed by Broadband Ocean Bottom Seismographs

宽带海底地震仪观测纪伊半岛浅层甚低频地震

• 发表时间: 2010
• 作者: Obana;K.;Manabu Morishige;Koichiro Obana
• 通讯作者: Koichiro Obana