An attempt to detect atmospheric free oscillations by a new array deployment of micro-barometers

尝试通过新的微气压计阵列部署来检测大气自由振荡

• 批准号: 17340135
• 负责人: FUKAO Yoshio
• 金额: $ 10.37万
• 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 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-17340135/
• 关键词: Earth's free oscillations; air pressure observation; atmospheric free oscillations; aero-acoustic waves

Network Construction(1) We replaced a 10 MHz clock of our micro-barometer system with a 50 MHz clock to increase resolution especially on a higher frequency side. We also developed a telemeter data-transmission system which enabled us to retrieve network data by PC at hand.(2) We installed the system at each of 14 stations of our network in the Kanto-Tokai districts. , which is now in routine operation. The amount of the data now available is not as large as originally anticipated because of the compelling change of the system design.(3) We examined the noise spectrum of air pressure fluctuation at each station and found a strange behavior of aero-acoustic tremor. We detected aero-gravity waves at 1-5mHz propagating from the west to east at a speed of 60 m/s.(4) We summarized the observational results obtained by the beginning of 2007, which were reported at an international conference in Greece.Results from Data Analyses and Theoretical Analyses(1) We developed an excitation model that can explain the observed resonance phenomenon of free oscillations between the solid Earth and the atmosphere, based on which we estimated the pressure amplitudes of atmospheric free oscillations to show that the detection is feasible.(2) We analyzed the IRIS seismograms to show that the excitation source of background free oscillations lies in the Pacific. The source moves seasonally. The sources are not limited to shallow seas but should extend to abyssal planes.(3) We detected background Love waves from tiltmeter network data in Japan. Kinetic energy ratio of Love to Rayleigh waves is approximately one. The background waves are strongest from ocean-continent borders, next from abyssal planes and weakest from continents.(4) We developed an excitation model attributing background Love and Rayleigh waves to topographic coupling of infragravity waves that effectively generates tangential stress acting on the presumed seafloor horizon.

网络构建(1) 我们将微气压计系统的 10 MHz 时钟替换为 50 MHz 时钟，以提高分辨率，尤其是在较高频率方面。我们还开发了遥测数据传输系统，使我们能够通过手头的 PC 检索网络数据。(2) 我们在关东东海地区的 14 个网络站中均安装了该系统。 ，目前已进入日常运行状态。由于系统设计发生了引人注目的变化，现在可用的数据量并不像最初预期的那么大。(3)我们检查了每个站点气压波动的噪声频谱，发现了一种奇怪的气动声颤动行为。我们探测到了1-5mHz的航空重力波，以60m/s的速度从西向东传播。(4)我们总结了2007年初在希腊举行的国际会议上报告的观测结果。数据分析和理论分析的结果(1) 我们开发了一个激励模型，可以解释观测到的固体地球和大气之间自由振荡的共振现象，在此基础上我们估计了大气自由振荡的压力幅度。 (2)对IRIS地震图进行分析,发现背景自由振荡的激发源位于太平洋。来源随季节变化。来源不仅限于浅海，还应延伸至深海位面。(3)我们从日本倾斜计网络数据中检测到了背景拉夫波。拉夫波与瑞利波的动能比大约为一。海洋-大陆边界的背景波最强，深海平面次之，大陆最弱。(4) 我们开发了一种激励模型，将背景洛夫波和瑞利波归因于次重力波的地形耦合，有效地产生作用在假定海底的切向应力。地平线。

项目成果

Seismic evidence for deep water transportation in the mantle

地幔深水输送的地震证据

• 发表时间: 2007
• 作者: Watada; Shingo
• 通讯作者: Shingo

Array observation of background atmospheric waves in the seismic band form 1mHz to 0.5Hz

1mHz至0.5Hz地震频带背景大气波阵列观测

• 发表时间: 2005
• 作者: N.Nishida; Y.fukao; S.Watada; N.Kobayashi; M.Tahira; N.Suda; K.Nawa; T.Oi; T.Kitajima
• 通讯作者: T.Kitajima

Source distribution of Earth's background free oscillations Reviewed journal

地球背景自由振荡的来源分布评论期刊

• 发表时间: 2007
• 作者: Fukao; Yoshio
• 通讯作者: Yoshio

Atmospheric pressure change associated with, the 2003 Tokachi-oki earthquake, Reviewed journal

与 2003 年十胜冲地震相关的大气压力变化，评论期刊

• 发表时间: 2006
• 作者: Watada; Shingo
• 通讯作者: Shingo

Atmospheric pressure change associated with the 2003 Tokachi-Oki earthquake.

与 2003 年十胜冲地震相关的大气压力变化。

• 发表时间: 2006
• 作者: Watada; S.; T.Kunugi; K.Hirata; H.Sugioka; K.Nishida; S.Sekiguchi; J.Oikawa; Y.Tsuji; H.Kanamori
• 通讯作者: H.Kanamori