日本地球惑星科学連合2025年大会

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[E] 口頭発表

セッション記号 S (固体地球科学) » S-MP 岩石学・鉱物学

[S-MP26] Supercontinents and Crustal Evolution

2025年5月29日(木) 10:45 〜 12:15 301B (幕張メッセ国際会議場)

コンビーナ:東野 文子(京都大学大学院理学研究科)、足立 達朗(九州大学)、Lakshmanan Sreehari(Department of Earth science Shimane University, Shimane, Matsue, Japan)、Chairperson:Sreehari Lakshmanan(Department of Earth science Shimane University, Shimane, Matsue, Japan)、竹原 真美(国立極地研究所)


11:15 〜 11:30

[SMP26-09] Review and update of the Archean crustal evolution of the Napier Complex, East Antarctica

*外田 智千1,2 (1.国立極地研究所、2.総合研究大学院大学)

キーワード:南極、太古代、ナピア岩体

The Archaean Napier Complex in East Antarctica is a 400 x 200 km large ancient craton that is characterized by a long crustal history with ages ranging from 3850 to 2450 Ma, and UHT~granulite-facies regional metamorphism at about 2550-2450 Ma. The dominant lithology is orthopyroxene-bearing felsic orthogneisses of tonalitic-trondhjemitic-granodioritic composition known as “Archean TTG”. Two-pyroxene granulite, garnet-bearing granitic gneiss, and other quartzo-feldspathic gneisses are major constituents. Various metasedimentary gneisses such as garnet gneiss, garnet-sillimanite gneiss, quartzite/siliceous gneiss, magnetite-quartz gneiss (meta-ironstone), and aluminous and magnesian gneisses occur.

The crustal history of the Napier Complex has been reviewed and discussed by Sheraton et al. (1987), Kelly and Harley (2005), Harley and Kelly (2007), and Hokada et al. (2008). Since then, a number of new data have been published, and this review summarizes the update of the crustal evolution of the Napier Complex.