DGPS 局を用いた地殻変動監視観測（2015 年）
GPS Observation for Monitoring Crustal Movements
at DGPS Stations in 2015
Summary – We have been carrying out monitoring of crustal movements in Japan through acontinuous GPS observation at DGPS stations employed by Maritime TrafficDepartment, JCG, since Jan. 1999. This paper reports the result of observations in2015.
Key words： GPS - DGPS - crustal movements
１．はじめに海上保安庁海洋情報部では，日本列島広域の地殻変動を監視し，地震予知の基礎資料を得るため，海上保安庁交通部ディファレンシャル GPS センターが運用するディファレンシャル GPS 局（以下，「DGPS 局」という．）の GPS 連続観測データを用いて 1999 年 1 月から解析運用を実施している．
本稿では，2015 年の解析結果について報告する．

２．観測及び解析方法
海上保安庁交通部ディファレンシャル GPS センターでは，全国 27 箇所の DGPS 局（第 1 図参照）において，30 秒間隔で GPS の連続データを取得している．データは専用回線により海上保安庁海洋情報部へ転送し，RINEX データに変換した後，精密基線解析ソフトウエア Bernese Ver.
5.0 を使用して解析を行っている．転送から解析までの一連の作業は，自動的に実行される．
解析は，下里水路観測所本土基準点（下里 H0：和歌山県東牟婁郡那智勝浦町）を基準として行い，衛星軌道暦は IGS 最終暦を使用した．
３．成果
2015 年 1 月～12 月の，下里 H0 を固定点とした各 DGPS 局までの斜距離，東西方向，南北方向及び高さ方向の変化を，第 2 図～第 15 図に示した．
変動の水平成分については，下里水路観測所本土基準点を基準として各 DGPS 局の水平方向変動ベクトルを第 16 図に示す．

GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第1図DGPS 局測点図

Fig.1 Locations of DGPS stations operated by JCG.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第2図下里基点での釧路埼及び網走の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.2 Results of continuous GPS measurements for Kushiro-saki and Abashiri relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第3図下里基点での宗谷岬及び積丹岬の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.3 Results of continuous GPS measurements for Souya-misaki and Shakotan-misaki relative toShimosato GPS station from January 1, 2015 to December 31, 2015.

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at DGPS stations in 2015

第4図下里基点での松前及び浜田の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.4 Results of continuous GPS measurements for Matsumae and Hamada relative to Shimosato GPSstation from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第5図下里基点での丹後及び舳倉島の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.5 Results of continuous GPS measurements for Tango and Hegura-shima relative to Shimosato GPS
station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第6図下里基点での酒田及び尻屋埼の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.6 Results of continuous GPS measurements for Sakata and Shiriya-saki relative to Shimosato GPS
station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第7図下里基点での金華山及び犬吠埼の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.7 Results of continuous GPS measurements for Kinkasan and Inubou-saki relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第8図下里基点での浦安及び剱埼の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.8 Results of continuous GPS measurements for Urayasu and Tsurugi-saki relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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at DGPS stations in 2015

第9図下里基点での八丈島及び名古屋の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.9 Results of continuous GPS measurements for Hachijo-shima and Nagoya relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 10 図下里基点での大王埼及び室戸岬の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.10 Results of continuous GPS measurements for Daiou-saki and Muroto-misaki relative toShimosato GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 11 図下里基点での江埼及び大浜の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.11 Results of continuous GPS measurements for E-saki and Ohama relative to Shimosato GPS
station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 12 図下里基点での瀬戸及び若宮の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.12 Results of continuous GPS measurements for Seto and Wakamiya relative to Shimosato GPS
station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 13 図下里基点での大瀬埼及び都井岬の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.13 Results of continuous GPS measurements for Ose-saki and Toi-misaki relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 14 図下里基点での中之島及び八重瀬の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.14 Results of continuous GPS measurements for Nakano-shima and Yaese relative to Shimosato
GPS station from January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 15 図下里基点での宮古島の GPS 連続観測結果 (2015/1/1～2015/12/31)

Fig.15 Results of continuous GPS measurements for Miyako-shima relative to Shimosato GPS stationfrom January 1, 2015 to December 31, 2015.

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GPS Observation for Monitoring Crustal Movements
at DGPS stations in 2015

第 16 図DGPS 局水平変動（下里水路観測所固定）

Fig.16 Horizontal displacements at DGPS stations operated by JCG relative to Shimosato GPS stationplotted as a solid star.

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