Investigation for geodetic detection of variation in crustal deformation near the subduction plate boundary

俯冲板块边界附近地壳变形变化的大地测量研究

• 批准号: 15340142
• 负责人: FUJIMOTO Hiromi
• 金额: $ 10.69万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15340142/
• 关键词: subduction plate boundary; plate motion; seismic coupling; seafloor geodetic observation; precise seafloor positioning; ocean bottom pressure monitoring; Japan trench; off Fukushima Prefecture; 宮城県沖; 非地震性すべり; 海底精密測位観察; 海陸プレート境界; 精密測位観測; 海底傾斜観

The objectives of this research program are to investigate for spatial and temporal variations in crustal deformation induced by the subducting plate motion through seafloor geodetic observation in the vicinity of the subduction plate boundary, and to estimate the repeatability of the seafloor geodetic observation.Repeated precise seafloor positioning based on sea surface KGPS positioning and underwater acoustic ranging has been carried out off Iwate and Miyagi prefectures, and has been initiated off Fukushima Prefecture. Judging from seismic activities off Fukushima, seismic coupling on the plate boundary in the region can be relatively weak. However, land-based GPS observation in these several years suggests strong coupling off Fukushima as well as off Miyagi. Although the estimated error is fairly large in the crustal deformation obtained from two-year observations, the result shows that the seismic coupling off Fukushima is as strong as that off Miyagi. The coupling off Fukushima may possibly show temporal variation.GPS/Acoustic (GPS/A) seafloor positioning off Kii Peninsula detected a large co-seismic crustal movement up to 30 cm associated with the 2004 earthquake (M7.4) off Kii Peninsula. The repeatability of the positioning obtained from an observation for two days is estimated to be about 3-5 cm. This value was larger than the estimated displacements at our GPS/A sites associated with the 2005 earthquake off Miyagi Prefecture. We confirmed that the value can be improved with higher GPS sampling.Long-term ocean bottom pressure monitoring was carried out off Iwate Prefecture under two crossover points of the satellite tracks for altimetry. The results coincide with recent five ocean tide models within 1.3 cm in terms of root sum square of vector differences for eight principal constituents. Although we have acquired know-how for long-term ocean bottom pressure monitoring, we need more research works to get long-term stability of pressure monitoring.

该研究计划的目的是调查通过俯冲板运动通过海底测量观测在俯冲板板边界附近进行的俯冲板运动引起的地壳变形的空间和时间变化，并估计了海底大地测量的重复性，基于确切的海面位置。 Iwate和Miyagi县，已于福岛县启动。从福岛的地震活动来看，该地区板界的地震耦合可能相对较弱。但是，在这几年中，陆基的GPS观察表明，与福岛和宫城脱离了强烈的耦合。尽管从两年观察结果获得的地壳变形中估计的误差相当大，但结果表明，福岛夫妇的地震耦合与宫城的地震耦合一样强。 fukushima耦合可能会显示时间变化。GPS/声学（GPS/A）在KII半岛附近定位的海底，检测到与2004年地震（M7.4）相关的大型共同的地壳运动。从观察结果获得两天的定位的可重复性估计约为3-5 cm。该值大于与宫城县2005年地震相关的GPS/A地点的估计位移。我们确认，通过较高的GPS采样，可以改善该值。长期的海洋底部压力监测是在卫星轨道的两个跨界点下进行高度计的iwate县进行的。该结果与八个主要成分的矢量差异的根总和之间的近期五个海水模型相吻合。尽管我们已经获得了长期海洋底部压力监测的专业知识，但我们需要更多的研究工作来获得压力监测的长期稳定性。

项目成果

Ocean bottom pressure observation off Sanriku and comparison with ocean tide models, altimetry, and barotropic signals from ocean models

• DOI: 10.1029/2006gl026706
• 发表时间: 2006-08
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Koji Matsumoto;Tadahiro Sato;Hiromi Fujimoto;Y. Tamura;M. Nishino;Ryota Hino;Toshihiro Higashi;Toshihiko Kanazawa

The 2003 M8.0 Tokachi-Oki earthquake - How much has the great event paid back slip debts?

• DOI: 10.1029/2003gl019021
• 发表时间: 2004-03-11
• 期刊: GEOPHYSICAL RESEARCH LETTERS
• 影响因子: 5.2
• 作者: Miura, S;Suwa, Y;Nishimura, T
• 通讯作者: Nishimura, T

三陸沖光ケーブル式海底地震津波観測亜システムによる津波観測

使用 Sanriku-Oki 光缆海底地震和海啸观测子系统进行海啸观测

• 发表时间: 2005
• 期刊: 月刊地球 37・3
• 作者: 日野亮太;藤本博巳;他;日野亮太
• 通讯作者: 日野亮太

Fujimoto, H.: "Seafloor geodesy and an ocean bottom cable system"Scientific Submarine Cable 2003 Workshop(SSC'03),25-27 June 2003,Tokyo, IEEE Catalogue. 03EX660. 251-254 (2003)

Fujimoto, H.：“海底大地测量和海底电缆系统”2003 年科学海底电缆研讨会(SSC03)，2003 年 6 月 25-27 日，东京，IEEE 目录。

Initial results of GPS/Acoustic seafloor positioning using a small towed buoy off Miyagi Prefecture, northeastern Japan

使用日本东北部宫城县附近的小型拖曳浮标进行 GPS/声学海底定位的初步结果

• 发表时间: 2006
• 期刊: J.Geod.Soc.Japan 52(2)
• 作者: Funakoshi;M.;Y.Osada;S.Miura;M.Nishino;A.Kuwano;R.Hino;H.Fujimoto
• 通讯作者: H.Fujimoto