13:45 〜 15:15
[MIS13-P03] Tectonic affinity of the Permo-Triassic Hida Belt in Japan: Review of recent progress in the geochronological research
キーワード：飛騨帯、ペルム紀ー三畳紀のテクトニクス、大和構造線
Since the finding of ultrahigh-pressure eclogites and garnet peridotites from the Chinese Sulu–Dabie orogen between the North China Craton (NCC) and South China Craton (SCC), the geological connection of the collisional orogen to East Asia has been discussed from various viewpoints by various researchers1,2. Because of the similarity of the metamorphic age, some studies considered the Japanese Hida Belt represents the eastern extension of the Sulu–Dabie orogen; consequently, geological and geochronological studies in the Hida Belt have mainly focused on the major tectonic framework of East Asia (East China, Korean Peninsula, and Far Eastern Russia). In this contribution, we outline the previous research on the Hida Belt and summarize the new geochronological studies in East Asia.
The Hida Belt represents a 'non-accreted' autochthonous basement in SW Japan. Permo-Triassic gneiss and granite of the belt along the Japan Sea have been considered to be the fragments of the continental margin basement before the Miocene Japan Sea opening. The metamorphic lithologies are mainly of amphibolite, calcareous gneiss, granitic gneiss, quartzofeldspathic gneiss, marble, and minor pelitic gneiss (garnet–sillimanite–biotite gneiss); rare kyanite- and staurolite-bearing pelitic schists intercalated with marble occurs in a small area. Past geochronological studies revealed that the regional upper amphibolite- to low-pressure granulite-facies metamorphism and related igneous activity were ∼260–230 Ma, and the younger undeformed granitic rocks were formed at ∼200–190 Ma3–7. The timing of the middle- and lower-crustal metamorphism of the Hida Belt is slightly older than either the UHP event or the post-collisional igneous activity of the Sulu Belt. Our age compilation of the Hida Belt indicated granitic intrusions would have occurred simultaneously with regional metamorphism. The latest geochronological comparison suggests that the Hida Belt can be correlated to the eastern Songliao block, Laoelin-Grodekov belt, and Yamato Ridge and was located in the immediate west of Greater South China8,9. The model seems to be consistent with the geochronological and geochemicalcharacteristics of the Permo-Triasic and Jurassic granitic rocks of the Korean Peninsula3,10. However, there are also some discrepancies in lithology, the nature of the metamorphism, and the zircon ages. In any case, the Hida Belt and the related Permo-Triassic East Asian continental basements unit still have the key to an understanding of the geodynamic process at the continental margin.
Reference
1 Ernst et al., 2007. Annu. Rev. Earth Planet. Sci. 35, 73–110. https://doi.org/10.1146/annurev.earth.35.031306.140146
2 Ishiwatari and Tsujimori, 2003. Isl. Arc 12. 190–206. https://doi.org/10.1046/j.1440-1738.2003.00390.x
3 Cho et al., 2021. Geosci. Front. 12, 101145. https://doi.org/10.1016/j.gsf.2021.101145
4 Horie et al., 2018. Chem. Geol. 484, 148–167. https://doi.org/10.1016/j.chemgeo.2017.12.016
5 Sano et al., 2000. Geochem. J. 34, 135–153. https://doi.org/10.2343/geochemj.34.135
6 Takahashi et al., 2018. Isl. Arc 27, e12220. https://doi.org/10.1111/iar.12220
7 Yamada et al., 2021. J. Mineral. Petrol. Sci. 116, 61–66. https://doi.org/10.2465/jmps.201125
8 Isozaki et al., 2021. Bull. Natl. Mus. Nat. Sci., Tokyo, C. 47, 25–39. https://doi.org/10.50826/bnmnsgeopaleo.47.0_25
9 Isozaki et al., 2023. Isl. Arc 32, e123475. https://doi.org/10.1111/iar.12475
10 Cheong and Jo, 2020, Gondwana Res. 88, 21–44. https://doi.org/10.1016/j.gr.2020.06.025
The Hida Belt represents a 'non-accreted' autochthonous basement in SW Japan. Permo-Triassic gneiss and granite of the belt along the Japan Sea have been considered to be the fragments of the continental margin basement before the Miocene Japan Sea opening. The metamorphic lithologies are mainly of amphibolite, calcareous gneiss, granitic gneiss, quartzofeldspathic gneiss, marble, and minor pelitic gneiss (garnet–sillimanite–biotite gneiss); rare kyanite- and staurolite-bearing pelitic schists intercalated with marble occurs in a small area. Past geochronological studies revealed that the regional upper amphibolite- to low-pressure granulite-facies metamorphism and related igneous activity were ∼260–230 Ma, and the younger undeformed granitic rocks were formed at ∼200–190 Ma3–7. The timing of the middle- and lower-crustal metamorphism of the Hida Belt is slightly older than either the UHP event or the post-collisional igneous activity of the Sulu Belt. Our age compilation of the Hida Belt indicated granitic intrusions would have occurred simultaneously with regional metamorphism. The latest geochronological comparison suggests that the Hida Belt can be correlated to the eastern Songliao block, Laoelin-Grodekov belt, and Yamato Ridge and was located in the immediate west of Greater South China8,9. The model seems to be consistent with the geochronological and geochemicalcharacteristics of the Permo-Triasic and Jurassic granitic rocks of the Korean Peninsula3,10. However, there are also some discrepancies in lithology, the nature of the metamorphism, and the zircon ages. In any case, the Hida Belt and the related Permo-Triassic East Asian continental basements unit still have the key to an understanding of the geodynamic process at the continental margin.
Reference
1 Ernst et al., 2007. Annu. Rev. Earth Planet. Sci. 35, 73–110. https://doi.org/10.1146/annurev.earth.35.031306.140146
2 Ishiwatari and Tsujimori, 2003. Isl. Arc 12. 190–206. https://doi.org/10.1046/j.1440-1738.2003.00390.x
3 Cho et al., 2021. Geosci. Front. 12, 101145. https://doi.org/10.1016/j.gsf.2021.101145
4 Horie et al., 2018. Chem. Geol. 484, 148–167. https://doi.org/10.1016/j.chemgeo.2017.12.016
5 Sano et al., 2000. Geochem. J. 34, 135–153. https://doi.org/10.2343/geochemj.34.135
6 Takahashi et al., 2018. Isl. Arc 27, e12220. https://doi.org/10.1111/iar.12220
7 Yamada et al., 2021. J. Mineral. Petrol. Sci. 116, 61–66. https://doi.org/10.2465/jmps.201125
8 Isozaki et al., 2021. Bull. Natl. Mus. Nat. Sci., Tokyo, C. 47, 25–39. https://doi.org/10.50826/bnmnsgeopaleo.47.0_25
9 Isozaki et al., 2023. Isl. Arc 32, e123475. https://doi.org/10.1111/iar.12475
10 Cheong and Jo, 2020, Gondwana Res. 88, 21–44. https://doi.org/10.1016/j.gr.2020.06.025