著者

飛田 幹男 宗包 浩志 海津 優 松坂 茂 黒石 裕樹 眞暗 良光 加藤 敏

出版者

日本測地学会

雑誌

測地学会誌 (ISSN:00380830)

巻号頁・発行日

vol.50, no.1, pp.27-37, 2004-03-25 (Released:2010-09-07)

参考文献数

14

被引用文献数

1

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The source of seasonal groundwater level variation, which is closely related to the variation of GPS vertical component, was investigated. We found that groundwater pumping for paddy field irrigation from May to August caused drawdown of groundwater level by 7m and this caused temporal subsidence by about 2 cm in Geographical Survey Institute, Tsukuba. Elastic deformation of gravel layers explains the process that groundwater level variation causes variation of ground height, because the height recovers completely and there is no delay between the two variations. The scale error of GEONET due to the seasonal height variation of the fixed GPS station at GSI is estimated to be±0.3 ppb.