JpGU-AGU Joint Meeting 2020

講演情報

[E] ポスター発表

セッション記号 S (固体地球科学) » S-GD 測地学

[S-GD01] 全球統合測地観測システム:変動する地球を監視する測地インフラ

コンビーナ:宮原 伐折羅(国土交通省国土地理院)、Richard S Gross(NASA Jet Propulsion Laboratory)

[SGD01-P06] Satellite Laser Ranging and GNSS observations in the Shimosato Hydrographic Observatory, Japan

*渡邉 俊一1瀬尾 徳常2中村 優斗1横田 裕輔3福良 博子4 (1.海上保安庁海洋情報部、2.第五管区海上保安本部下里水路観測所、3.東京大学生産技術研究所、4.第八管区海上保安本部)

キーワード:人工衛星レーザー測距、GNSS、LAGEOS、C5++、コロケーション

The Shimosato Hydrographic Observatory (SHO) of Japan Coast Guard, located in the southernmost part of Wakayama Prefecture, operates Satellite Laser Ranging (SLR) observations since 1982 as well as continuous GNSS observation. Collected SLR and GNSS data are transferred to the International Laser Ranging Service (ILRS) and the International GNSS Service (IGS), respectively. The transferred data contribute to the construction and development of the International Terrestrial Reference Frame (ITRF). The SHO which operates two kinds of global geodetic techniques is now one of the Global Geodetic Observing System (GGOS) sites.

In order to enhance the usability of the SLR observation system, the SHO has updated its laser ranging equipment in 2018. We installed a laser oscillator with changeable pulse repetition rate up to 1 kHz (i.e., kilohertz laser), by which we can collect the ranging data at a higher rate than by the former one with a pulse repetition rate of 5 Hz. The relevant updates on the control devices contribute to the simplification of SLR operation.

In this presentation, we first describe the summary of our laser ranging system update in the SHO, and then show the geodetic results of SLR and GNSS positioning at the SHO. The SLR monthly positions were calculated using LAGEOS-1 and LAGEOS-2 ranging data with the analysis software C5++ (Otsubo et al., 2016, Earth Planets Space). The results clearly reproduced the coseismic displacements due to the 2004 southeastern off Kii Peninsula earthquakes (M7.4 and M6.9) and the 2011 Tohoku-oki earthquake (M9.0). In addition, significant postseismic displacements following the Tohoku-oki earthquake were also obtained.
Acknowledgments: Dr. Otsubo of the Hitotsubashi University provided us the analysis software “C5++” and the adjusted data/parameters for SHO’s data analysis.