日本地球惑星科学連合2019年大会

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セッション記号 S (固体地球科学) » S-SS 地震学

[S-SS16] 地殻変動

2019年5月26日(日) 13:45 〜 15:15 A03 (東京ベイ幕張ホール)

コンビーナ:大園 真子(北海道大学大学院理学研究院附属地震火山研究観測センター)、落 唯史(国立研究開発法人産業技術総合研究所 地質調査総合センター 活断層・火山研究部門)、加納 将行(東北大学理学研究科)、座長:田部井 隆雄(高知大学理工学部地球環境防災学科)、伊藤 武男

14:15 〜 14:30

[SSS16-14] The kinematic model along the Sumatran fault using a new dense GNSS observation (AGNeSS+) in Banda Aceh

*伊藤 武男1田部井 隆雄2木股 文昭3大久保 慎人2山品 匡史2Cecep Pratama4Didik Sugiyanto5Mukusin Umar5Nazli Ismail5Irwandi Nurdin5 (1.名古屋大学、2.高知大学、3.東濃地震科学研究所、4.ガジャマダ大学、5.シアクラ大学)

キーワード:GNSS、バンダアチェ、ブロック運動モデル

The 2004 Sumatra-Andaman earthquake (Mw 9.2) has occurred along the Sunda trench. In Banda Aceh district, evaluation of the earthquake generation potential along the Sumatran fault is highly urgent because of a large fault slip rate, the lack of major earthquakes for more than 100 years and recent Coulomb stress increase on the fault due to the 2004 event. After the 2004 event, we have deployed the Aceh GNSS Network for the Sumatran fault System (AGNeSS), which consists of 24 GNSS sites. AGNeSS have releveled the along-strike variations of elastic coupling and creeping along the Sumatran fault system (Ito et al.,2012). Recently, seismic activity is increasing around the Seulimeum fault. So, we try to evaluate the earthquake potential around the Seulimeum fault.

However, AGNeSS have already passed a decade since developed, and the site condition of GNSS sites is disintegrating. So, we extend AGNeSS, which consists of new dense 25 GNSS site (we call the AGNeSS+). We developed the new GNSS site in 2016. The AGNeSS+ aims to evaluate the seismic potential along the Seulimeum fault, where is close to urban of Banda Aceh province. The new dense GNSS site has two profiles crossing the Seulimeum fault. The length and the average interval of the profile are about 30km and about 3km, respectively. Also, an interval of GNSS site near the Seulimeum fault is shorter.

In this study, we show the first result of AGNeSS+, and a block motion model around the Banda Aceh area base on AGNeSS+. We developed the block motion model based on geological information. The Banda Aceh city locates between two fault segments, which is Aceh and Seulimeum segments. The block motion model considers these block boundary. In this presentation, we show the first results of slip deficit along Seulimeum segments and kinematic block motion.