Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin

The belt boundary thrust within the Cretaceous–Neogene accretionary complex of the Shimanto Belt, southwestern Japan, extends for more than ~ 1 000 km along the Japanese islands. A common understanding of the origin of the thrust is that it is an out of sequence thrust as a result of continuous accr...

Full description

Saved in:
Bibliographic Details
Main Authors: Kimura, Gaku, Kitamura, Yujin, Yamaguchi, Asuka, Kameda, Jun, Hashimoto, Yoshitaka, Hamahashi, Mari
Other Authors: Earth Observatory of Singapore
Format: Article
Language:English
Published: 2019
Subjects:
Online Access:https://hdl.handle.net/10356/90311
http://hdl.handle.net/10220/50479
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Nanyang Technological University
Language: English
id sg-ntu-dr.10356-90311
record_format dspace
spelling sg-ntu-dr.10356-903112020-09-26T21:25:06Z Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin Kimura, Gaku Kitamura, Yujin Yamaguchi, Asuka Kameda, Jun Hashimoto, Yoshitaka Hamahashi, Mari Earth Observatory of Singapore Accretionary Prism East Asian Margin Tectonics Science::Geology The belt boundary thrust within the Cretaceous–Neogene accretionary complex of the Shimanto Belt, southwestern Japan, extends for more than ~ 1 000 km along the Japanese islands. A common understanding of the origin of the thrust is that it is an out of sequence thrust as a result of continuous accretion since the late Cretaceous and there is a kinematic reason for its maintaining a critically tapered wedge. The timing of the accretion gap and thrusting, however, coincides with the collision of the Paleocene–early Eocene Izanagi–Pacific spreading ridges with the trench along the western Pacific margin, which has been recently re‐hypothesized as younger than the previous assumption with respect to the Kula‐Pacific ridge subduction during the late Cretaceous. The ridge subduction hypothesis provides a consistent explanation for the cessation of magmatic activity along the continental margin and the presence of an unconformity in the forearc basin. This is not only the case in southwestern Japan, but also along the more northern Asian margin in Hokkaido, Sakhalin, and Sikhote‐Alin. This Paleocene–early Eocene ridge subduction hypothesis is also consistent with recently acquired tomographic images beneath the Asian continent. The timing of the Izanagi–Pacific ridge subduction along the western Pacific margin allows for a revision of the classic hypothesis of a great reorganization of the Pacific Plate motion between ~ 47 Ma and 42 Ma, illustrated by the bend in the Hawaii–Emperor chain, because of the change in subduction torque balance and the Oligocene–Miocene back arc spreading after the ridge subduction in the western Pacific margin. Published version 2019-11-29T07:57:58Z 2019-12-06T17:45:27Z 2019-11-29T07:57:58Z 2019-12-06T17:45:27Z 2019 Journal Article Kimura, G., Kitamura, Y., Yamaguchi, A., Kameda, J., Hashimoto, Y., & Hamahashi, M. (2019). Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin. Island Arc, 28(5). doi:10.1111/iar.12320 1038-4871 https://hdl.handle.net/10356/90311 http://hdl.handle.net/10220/50479 10.1111/iar.12320 en Island Arc © 2019 The Authors. Island Arc Published by John Wiley & Sons Australia, Ltd. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made. 15 p. application/pdf
institution Nanyang Technological University
building NTU Library
country Singapore
collection DR-NTU
language English
topic Accretionary Prism
East Asian Margin Tectonics
Science::Geology
spellingShingle Accretionary Prism
East Asian Margin Tectonics
Science::Geology
Kimura, Gaku
Kitamura, Yujin
Yamaguchi, Asuka
Kameda, Jun
Hashimoto, Yoshitaka
Hamahashi, Mari
Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
description The belt boundary thrust within the Cretaceous–Neogene accretionary complex of the Shimanto Belt, southwestern Japan, extends for more than ~ 1 000 km along the Japanese islands. A common understanding of the origin of the thrust is that it is an out of sequence thrust as a result of continuous accretion since the late Cretaceous and there is a kinematic reason for its maintaining a critically tapered wedge. The timing of the accretion gap and thrusting, however, coincides with the collision of the Paleocene–early Eocene Izanagi–Pacific spreading ridges with the trench along the western Pacific margin, which has been recently re‐hypothesized as younger than the previous assumption with respect to the Kula‐Pacific ridge subduction during the late Cretaceous. The ridge subduction hypothesis provides a consistent explanation for the cessation of magmatic activity along the continental margin and the presence of an unconformity in the forearc basin. This is not only the case in southwestern Japan, but also along the more northern Asian margin in Hokkaido, Sakhalin, and Sikhote‐Alin. This Paleocene–early Eocene ridge subduction hypothesis is also consistent with recently acquired tomographic images beneath the Asian continent. The timing of the Izanagi–Pacific ridge subduction along the western Pacific margin allows for a revision of the classic hypothesis of a great reorganization of the Pacific Plate motion between ~ 47 Ma and 42 Ma, illustrated by the bend in the Hawaii–Emperor chain, because of the change in subduction torque balance and the Oligocene–Miocene back arc spreading after the ridge subduction in the western Pacific margin.
author2 Earth Observatory of Singapore
author_facet Earth Observatory of Singapore
Kimura, Gaku
Kitamura, Yujin
Yamaguchi, Asuka
Kameda, Jun
Hashimoto, Yoshitaka
Hamahashi, Mari
format Article
author Kimura, Gaku
Kitamura, Yujin
Yamaguchi, Asuka
Kameda, Jun
Hashimoto, Yoshitaka
Hamahashi, Mari
author_sort Kimura, Gaku
title Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
title_short Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
title_full Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
title_fullStr Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
title_full_unstemmed Origin of the early Cenozoic belt boundary thrust and Izanagi–Pacific ridge subduction in the western Pacific margin
title_sort origin of the early cenozoic belt boundary thrust and izanagi–pacific ridge subduction in the western pacific margin
publishDate 2019
url https://hdl.handle.net/10356/90311
http://hdl.handle.net/10220/50479
_version_ 1681056302202093568