日本地球惑星科学連合2021年大会

講演情報

[J] 口頭発表

セッション記号 S (固体地球科学) » S-GD 測地学

[S-GD01] 測地学・GGOS

2021年6月4日(金) 09:00 〜 10:30 Ch.22 (Zoom会場22)

コンビーナ:松尾 功二(国土地理院)、横田 裕輔(東京大学生産技術研究所)、大坪 俊通(一橋大学)、座長:松尾 功二(国土地理院)、服部 晃久(総合研究大学院大学)

10:00 〜 10:15

[SGD01-05] 南極ジャンボゴ基地における重力測定と異なる種類の相対重力計定数検定

*福田 洋一1、奥野 淳一1、土井 浩一郎1、Lee Choon-ki2 (1.情報・システム研究機構 国立極地研究所、2.韓国極地研究所)

キーワード:絶対重力計、超伝導重力計、ラコストD型重力計、定数検定、ジャンボゴ基地

We conducted gravity observations using FG5-210 absolute gravimeter (AG) and LCR D-58 relative gravimeter, at Korean Jang Bogo Station (JBS), in 2019-2020 Austral summer season.

The AG measurements were successfully done at two points named JBSAG1 and JBSAG2, and obtained about 19000 and 14400 drops of data, respectively, with the measurement precisions better than 0.4 µGal (1 µGal=10-8 ms-2). In addition, the relative gravity measurements were conducted at 10 newly established gravity points in JBS to supplement the absolute gravity points.

In JBS, superconducting gravimeter (SG) observation with iGrav-021 has been continued since 2016. Since SG is a relative gravimeter, the calibration of the scale factor is essential for long-term gravity monitoring. Moreover, D-58 is also required the scale factor calibration as well. To calibrate the scale factors of these gravimeters, we first estimated the iGrav-021scale factor by the parallel observations with the FG5-210. And then the D-58 scale factor were indirectly estimated by the parallel observations with iGrav-021. This procedure worked well, and these calibrations should ensure the accurate gravity monitoring in the future.
Since we have already reported the details about the AG measurements at the 2020 JpGU meeting, we will mainly report the results of relative gravity measurements and the scale factor calibrations in this paper.