气候变化领域集成服务门户(CCPortal): Upper-plate controls on subduction zone geometry, hydration and earthquake behaviour

CCPortal

DOI	10.1038/s41561-021-00879-x
	Upper-plate controls on subduction zone geometry, hydration and earthquake behaviour
	Arnulf A.F.; Bassett D.; Harding A.J.; Kodaira S.; Nakanishi A.; Moore G.
发表日期	2022
ISSN	1752-0894
卷号	15 期号:2
英文摘要	Many characteristics of the incoming oceanic lithosphere, such as its age, rigidity, fabric orientation or sediment thickness, are often cited as important properties controlling the geometry, state of stress, dynamics and hazard potential of subduction zones, yet the links between upper-plate structures and subduction zone processes remain poorly understood. Here we report that high forearc wavespeeds (vP greater than 6.6 km s−1) beneath 8,000 km2 of Kii Peninsula are associated with the Kumano pluton. We show that the dense, high-rigidity Kumano pluton generates a large vertical load, which forces the incoming Philippine Sea Plate to subduct with a trajectory that is a factor of two steeper than adjacent regions. Beneath the region of maximum curvature and faulting of the Philippine Sea Plate, reduced mantle velocities (6.5–7.5 km s−1) within a 25-km-thick, 100-km-wide region at 5–30-km sub-Moho depths may reflect serpentinization (more than 40% antigorite) of the subducting mantle and enhanced porosity from bending stresses. We further report that great (larger than Mw 8) earthquakes nucleated from the flanks of the Kumano pluton in 1944 and 1946. Our study demonstrates the profound impact of upper-plate structures on the geometry, hydration state and segmentation of large megathrust earthquakes at subduction zones. © 2022, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	earthquake event; faulting; geometry; hydration; Philippine Sea plate; porosity; segmentation; serpentinization; subduction zone; Honshu; Japan; Kii Peninsula; Kinki; Kumano; Mie
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/250796
作者单位	Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, United States; GNS Science, Lower Hutt, New Zealand; Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, UCSD, La Jolla, CA, United States; Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan; Department of Earth Sciences, University of Hawai’i at Manoa, Honolulu, HI, United States
推荐引用方式 GB/T 7714	Arnulf A.F.,Bassett D.,Harding A.J.,et al. Upper-plate controls on subduction zone geometry, hydration and earthquake behaviour[J],2022,15(2).
APA	Arnulf A.F.,Bassett D.,Harding A.J.,Kodaira S.,Nakanishi A.,&Moore G..(2022).Upper-plate controls on subduction zone geometry, hydration and earthquake behaviour.Nature Geoscience,15(2).
MLA	Arnulf A.F.,et al."Upper-plate controls on subduction zone geometry, hydration and earthquake behaviour".Nature Geoscience 15.2(2022).