日本地質学会第130年学術大会

講演情報

シンポジウム

S1.[シンポ]環太平洋地域における白亜紀フレアアップ

[3oral301-07] S1.[シンポ]環太平洋地域における白亜紀フレアアップ(一般公募なし)

2023年9月19日(火) 10:00 〜 12:00 口頭第3会場 (4共30:吉田南4号館)

座長:河上 哲生(京都大学大学院理学研究科)、中村 佳博(産総研)

11:00 〜 11:30

[S1-O-5] [招待講演]Linking Japan-NW Pacific plate tectonics and arc magmatism since the Cretaceous

*Wu Jonny1、Wu Tsung-Jui2、Yamaoka Ken3 (1. University of Houston, USA、2. Institute of Earth Sciences, Academia Sinica, Taiwan、3. Research Institute of Geology and Geoinformation, Geological survey of Japan (GSJ))

キーワード:subduction、Pacific、Izanagi、magmatism、tomography

Japan has been situated along an active subduction zone since at least the Cretaceous. Here we review the emerging use of seismic tomography to map subducted plates (i.e. slabs) now lying within the mantle under Japan to reconstruct Japan-NW Pacific plate tectonics since the Cretaceous. We build a ‘tomographic’ plate tectonic reconstruction and summarize the ages, kinematics, thermal regime, and likely identity of the plates outboard of Japan since the Cretaceous. Our plate reconstruction is compared against relatively independent arc magmatism along Japan and surrounding regions from 140 to 0 Ma. We explore possible links between arc magmatic flare-ups and lulls, magmatic ages, spatiotemporal patterns, and geochemical compositions and Japan-NW Pacific plate tectonics.