JpGU-AGU Joint Meeting 2017

講演情報

[EJ] 口頭発表

セッション記号 S (固体地球科学) » S-GD 測地学

[S-GD02] [EJ] 重力・ジオイド

2017年5月24日(水) 10:45 〜 12:15 A05 (東京ベイ幕張ホール)

コンビーナ:山本 圭香(国立天文台)、宮崎 隆幸(国土交通省国土地理院)、座長:潮見 幸江(群馬大学大学院理工学府)、座長:今西 祐一(東京大学地震研究所)

10:45 〜 11:00

[SGD02-07] Absolute gravity measurements in New Zealand (2nd report)

*福田 洋一1瀧口 博士2西島 潤3風間 卓仁1Stagpoole Vaughan4Gulyaev Sergei5Natusch Tim5Amos Matt6 (1.京都大学大学院理学研究科、2.情報通信研究機構電磁波計測研究所、3.九州大学大学院工学研究院、4.GNS Science、5.Institute for Radio Astronomy and Space Research, Auckland University of Technology、6.Land Information New Zealand)

キーワード:ニュージーランド、絶対重力測定、重力網、重力変化、ニュージランド南アルプス、カイコウラ地震

To enhance and extend the absolute gravity (AG) measurements in New Zealand, we had conducted AG measurements using a FG5 (#210 of Kyoto University) in January and March 2016 as reported in 2016 JpGU meeting. The measurements were made at three points in North Island and five points in South Island. To compliment the AG measurements, we also conducted relative measurements using a LaCoste & Romberg G-meter (#680) at five points from Bilham et al. (2016) in Southern Alps. Among them, two points are located near the summits and only accessible by a helicopter. Thus we could conduct a single loop measurement only, due to restricted time and weather condition in 2016.
Although we have not conducted AG measurements in 2017, relative measurements using two LaCoste & Romberg G-meters (#680 and #805) have been conducted at four points near the summits including the two points occupied in 2016, and conducted two loops of the measurements for those points. In addition to these, we conducted the measurements at most of the AG points occupied in 2016 and some additional points from Stagpoole et al. (2015) for the calibration of the scale factors of the gravimeters, and the gravity connections to the spare points near the AG points. Moreover, for planning the AG measurements in the area of 2016 Kaikoura earthquake (Mw 7.8), we conducted test measurements at a few points where huge uplifts have been observed. In this talk, we present the results in 2017, and the future observation plan particularly in the area of Kaikoura earthquake. This study was partially supported by JSPS KAKENHI Grant No. 15H05205.