Research on Active monitoring of crustal state using phased array source

相控阵源地壳状态主动监测研究

• 批准号: 17340129
• 负责人: YAMAOKA Koshun
• 金额: $ 9.6万
• 依托单位: Nagoya University (2007)The University of Tokyo (2005-2006)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17340129/
• 关键词: Earthquake; Volcano; Controlled source; Temporal change; Crustal structure; 固体地球物理学; 自然現象観測・予測; テクトニクス; モニタリング; 物理探査; 能動震源; 地殻モニタリング; アクロス; 時間変化

We have investigated the efficiency of controlled seismic source with phased array for the active monitoring within the earth's crust. The purpose of the research is to investigate (1) the efficiency of the phased array, (2) efficiency of source and receiver array, (3) effect of heterogeneity of the structure and (4) detectability of temporal change with long-term operation.To achieve these purpose, we have re-install the ACROSS (Accurately-Controlled Routine-Operated Signal System) vibrators in the Mikawa observatory of Nagoya University. The vibrator has been being operated in Kagamihara, in Gifu prefecture, and consists of four vibrator units. It was intended to generate a linear motion in arbitrary horizontal direction. As this function has been achieved in different way, we relocate the vibrator from original site to Toyohashi in order to investigate the effect of phased array. In Toyohashi site two vibrator units are separately deployed with 20m separation. The two units are operated in the same time and same frequency range with slight difference in center frequency. The operation is made using PCs that are synchronized to GPS time. The phased array requires several other tips for trouble-less operation, including newly-designed oil lubricator, signal transmission line, anti-vibration insulator, etc. After we have checked operation ability to fix the problem, we installed receiver arrays around the source with a distance of about one kilometer. We operated the source for two months to check the effect of source and receiver arrays. The result of analysis will be soon reported in papers and meetings.

我们研究了相控阵可控震源在地壳内主动监测中的效率。研究的目的是为了研究(1)相控阵的效率，(2)源和接收器阵列的效率，(3)结构不均匀的影响，(4)随长期运行时间变化的可探测性。为了实现这些目的，我们在名古屋大学宫川天文台重新安装了跨(精确控制的常规操作信号系统)可控震源。该可控震源一直在岐阜县神宫原市运行，由四个可控震源单元组成。它的目的是在任意水平方向上产生线性运动。由于这一功能的实现方式不同，为了研究相控阵的效果，我们将可控震源从原址重新安置到丰桥。在丰桥现场，两个可控震源单元被单独部署，间隔20米。这两个单元在相同的时间和相同的频率范围内工作，但中心频率略有不同。操作是使用与GPS时间同步的PC进行的。相控阵还需要其他几个无故障运行的技巧，包括新设计的润滑油、信号传输线、防振绝缘体等。在我们检查了操作能力以修复问题后，我们在震源周围安装了距离约一公里的接收器阵列。我们对震源运行了两个月，以检查震源和接收器阵列的效果。分析结果将很快在论文和会议中报告。

项目成果

Feasibility experiment for Active Monitoring of Inter-plate Coupling in Tokai region

东海地区板间耦合主动监测可行性试验

• 发表时间: 2005
• 作者: Watanabe;T.;Ikuta;R.;Soma;T.;Saiga;A.;Miyajima;R.;Fujii;N.;Yamaoka;K.;Tsuruga;K.;Kunitomo;T.;Hasada;Y.;Kasahara;J.;Kumazawa;M;Satomura;M
• 通讯作者: M

Detection of Reflected Waves from Plate Boundary Using ACROSS Source and Seismic Array

使用跨源和地震阵列检测板块边界的反射波

• 发表时间: 2005
• 作者: Soma;T.;Watanabe;T.;Ikuta;R.;Saiga;A.;Miyajima;R.;Yamaoka;K.;Tsuruga;K.;Kunitomo;T.;Hasada;Y.;Kasahara;J.;Satomura;M.;Kumazawa;M.;Fujii;N.,
• 通讯作者: N.,

Monitoring Experiment in Tokai, Japan: ACROSS source designed for a phased array,

日本东海的监测实验：专为相控阵设计的跨源，

• 发表时间: 2005
• 作者: Yamaoka;K.;Watanabe;T.;Fujii;N.;Ikuta;R.;Miyajima;R.
• 通讯作者: R.

Strategy of earthquake prediction research in Japan and the role of active monitoring

日本地震预测研究策略及主动监测的作用

• 发表时间: 2005
• 期刊: Proceedings of the Active Geophysical Monitoring of the earth lithosphere
• 作者: Yamaoka;K
• 通讯作者: K

Interpretation of frequency dependence in transfer functions acquiredby seismic ACROSS

地震 ACROSS 获取的传递函数中频率依赖性的解释

• 发表时间: 2007
• 作者: Hasada Y. Watanabe T. Yamaoka K.;et. al.
• 通讯作者: et. al.