Logn-term, Absolute Measurement of the 3 Componets of Geomagnetic Field and Establishment of Fixed Geomagnetic Stations at the Sea Floor

地磁场三分量的对数绝对测量及海底固定地磁站的建立

• 批准号: 60840006
• 负责人: SEGAWA Jiro
• 金额: $ 18.56万
• 依托单位: The Univerisity of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60840006/
• 关键词: Sea flooe mabnetic field; 3-component magnetometer; proton magnetometer; Sea floor observation station; Submersible; Sea floor electric field recorder; 海底電位差計; フラックスゲート型磁力計; 海底観測; 磁場絶対測定; 地磁気3成分; 海底地磁気定点; 3成分海底磁力計; オーバーハウザー

Main results we have obtained through this study can be summatized as follows: (1) A small 3-component fluxgate magnetometer(OBM-S5) was developed. As this meter is deiven by a battery installed separately from the sensor housing is is not affected by the magnetization battery and can continue measurement for a longer time.(2) Another Fluxgate magnetometer (OBM-C3) whose sensor was installed about I m above the electronics was developed in order to remove the magnetic effect from the electronics components completely. (3) A proton magnetometer for sea floor use (OBP) was developed to be used for calibration of the fluxgate magnetometer. (4) An electric field recorde for the sea floor (OBE) was developed.Using the equipments mentiones above a dea floor experiment was conductod in the area of the Izu-Bonin ridge alon the parallel 33゜N from August to October 1986 (about 75 days). In the next year from July to October (78 days) another sea floor experiment was conducted in the area a little south of the last area along the parallel 31゜N Through these experiments is was proven that thr fluxgate magnetometer could be calibrated with the aid of a proton marnetometer installed nearby. This result will ensure the plausibility of making absolute measurements of 3-component magnetic field at the seq floor. Another importani result of our study is the installation of thw Ocean Bottom Observation Station in the Sagami Bay from October to November 1987. This station made of non-magnetic concrete, equipped with an acoustic transponder, works as a permanent oceam bottom platrofm reaccessible at any timw. In November the Oceam Bottom Platform was visited by a manned submersible of the Japan Matine Scienece and Technoloby Center and it was confirmed that the platform setteld in a good condition.

主要研究成果如下：（1）研制了一台小型三分量磁通门磁力仪（OBM-S5）。由于该仪表由与传感器外壳分开安装的电池驱动，因此不受磁化电池的影响，可以持续更长时间的测量。(2)另一种磁通门磁力计（OBM-C3）的传感器安装在电子设备上方约1米处，以完全消除电子元件的磁效应。(3)研制了一种海底用质子磁力仪，用于校准磁通门磁力仪。(4)研制了海底电场记录仪（OBE），并利用该仪器于1986年8月至10月在伊豆-小笠原海岭地区沿北纬33度进行了海底电场实验（约75天）。第二年7月至10月（78天），又在沿着北纬31度线偏南的海域进行了一次海底实验。通过实验证明，磁通门磁力仪可以用附近的质子磁力仪进行刻度。这一结果将确保在seq地板上进行三分量磁场绝对测量的可行性。我们研究的另一个重要结果是1987年10月至11月在相模湾建立了海底观测站。这个空间站由非磁性混凝土制成，配备了一个声波应答器，作为一个永久的海底平台，可以在任何时间重新访问。11月，日本Matine科学技术中心的一艘载人潜水器访问了海底平台，并确认该平台处于良好状态。

项目成果

SEGAWA, Jiro: "A sea floor magnetometer Model OBM-S4" Journal of Geodetic Society of Japan. 32. 248-273 (1986)

SEGAWA, Jiro：“海底磁力计 OBM-S4 型”，日本大地测量学会杂志。

SEGAWA, Jiro: "Measutement of geomagnetic field by Ocean Bottom Proton Magnetometer (I)." Read at 66th Assembly of the Geodetic Society of Japan 1986 at Mizusawa. (1986)

SEGAWA, Jiro：“海底质子磁力计测量地磁场（I）。”

SEGAWA,Jiro: Journal of Geodetic Society of Japan. 32. 248-273 (1986)

SEGAWA，二郎：日本大地测量学会杂志。

日本地球電気磁気学会誌. (1986)

日本地电磁学会会刊（1986 年）。

KOIZUMI, Kin-ichiro: "Measutement of geomagnetic filed by an Ocean Bottom Magnetometer and comparison with the measurement of a Fluxgate magnetometer." To be read at the spring assembly of the Geomagnetism and Terrestrial;Planetary Sciences 1988 at Kogane

KOIZUMI、Kin-ichiro：“海底磁力计测量地磁场并与磁通门磁力计测量结果进行比较。”