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タイトル: | Spatiotemporal evolution of magmatic pulses and regional metamorphism during a Cretaceous flare-up event: Constraints from the Ryoke belt (Mikawa area, central Japan) |
著者: | Takatsuka, Kota Kawakami, Tetsuo https://orcid.org/0000-0002-5921-5562 (unconfirmed) Skrzypek, Etienne Sakata, Shuhei Obayashi, Hideyuki Hirata, Takafumi |
著者名の別形: | 河上, 哲生 |
キーワード: | Continental crust formation Flare-ups Plutono-metamorphic evolution U–Pb zircon dating Low-P/T type metamorphism Granite |
発行日: | May-2018 |
出版者: | Elsevier BV |
誌名: | Lithos |
巻: | 308–309 |
開始ページ: | 428 |
終了ページ: | 445 |
抄録: | The spatiotemporal relationship between granitoid intrusions and low-pressure/temperature type regional metamorphism in the Ryoke belt (Mikawa area) is investigated to understand the tectono-thermal evolution of the upper- to middle-crust during a Cretaceous flare-up event at the Eurasian active continental margin. Three plutono-metamorphic stages are recognized; (1) 99–84 Ma: intrusion of granitoids (99–95 Ma pulse) into the upper crust and high-T regional metamorphism reaching sillimanite-grade (97.0 ± 4.4 Ma to 88.5 ± 2.5 Ma) in the middle crust, (2) 81–75 Ma: intrusion of gneissose granitoids (81–75 Ma Ma pulse) into the middle crust at ~19–24 km depth, and (3) 75–69 Ma: voluminous intrusions of massive to weakly-foliated granitoids (75–69 Ma pulse) at ~9–13 km depth and formation of contact metamorphic aureoles. Cooling of the highest-grade metamorphic zone below the wet solidus of granitic rocks is estimated at 88.5 ± 2.5 Ma. At ca. 75 Ma, the upper-middle crustal section underwent northward tilting, resulting in the exhumation of regional metamorphic zones to ~9–13 km depth. Although the highest-grade metamorphic rocks and the 99–95 Ma pulse granitoids preserve similar U–Pb zircon ages, the absence of spatial association suggests that the regional metamorphic zones were mainly produced by a transient thermal anomaly in the mantle and thermal conduction through the crust, supplemented by localized advection due to granitoid intrusions. The successive emplacement of granitoids into shallow, deep and shallow levels of the crust was probably controlled by the combination of change in thermal structure of the crust and tectonics during granitoid intrusions. |
著作権等: | © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ The full-text file will be made open to the public on 01 May 2020 in accordance with publisher's 'Terms and Conditions for Self-Archiving'.This is not the published version. Please cite only the published version. この論文は出版社版でありません。引用の際には出版社版をご確認ご利用ください。 |
URI: | http://hdl.handle.net/2433/231107 |
DOI(出版社版): | 10.1016/j.lithos.2018.03.018 |
出現コレクション: | 学術雑誌掲載論文等 |
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