气候变化领域集成服务门户(CCPortal): Strain partitioning across a subduction thrust fault near the deformation front of the Hikurangi subduction margin, New Zealand: A magnetic fabric study on IODP Expedition 375 Site U1518

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DOI	10.1016/j.epsl.2020.116322
	Strain partitioning across a subduction thrust fault near the deformation front of the Hikurangi subduction margin, New Zealand: A magnetic fabric study on IODP Expedition 375 Site U1518
	Greve A.; Kars M.; Zerbst L.; Stipp M.; Hashimoto Y.
发表日期	2020
ISSN	0012821X
卷号	542
英文摘要	Understanding the distribution of strain along thrust and splay faults in active accretionary systems is crucial to understand the mechanical properties of the sediments and the strength of the fault zone and its slip behavior. This paper investigates the distribution of strain through sediment compaction and texture development across the Pāpaku fault, a major splay fault near the deformation front of the Hikurangi subduction margin, New Zealand using the anisotropy of magnetic susceptibility technique (AMS). International Ocean Discovery Program Site U1518 penetrated hanging wall, fault zone and footwall sequences to a maximum depth of 484.9 meters below seafloor. A total of 330 discrete samples was subjected to AMS measurements and magnetic remanence data used to reconstruct the axial orientation of each sample in a geographic reference frame. The AMS display distinct fabric differences between hanging wall, through the fault zone and footwall domains, demonstrating that strain is partitioned across the fault zone. Hanging wall sequences show a strike-parallel northeasterly lineation of Kmax and weakly prolate shapes, typical for a component of northeast-southwest lateral shortening. In contrast, footwall sequences are more oblate and show a clustering of Kmax in northerly direction. This demonstrates that strain in the footwall is dominated by gravitational loading, however a component of sub-horizontal east-westerly strain, parallel to the convergence direction of the Pacific Plate exists. Strain decoupling between hanging- and footwall sequences occurs near the top of the Pāpaku fault zone. Differences in the degree of magnetic susceptibility between footwall sediments incorporated into the fault zone, and the underlying undeformed footwall sequences are indicative for the progressive dewatering of the underconsolidated footwall sequences. © 2020 The Author(s)
关键词	accretionary system anisotropy of magnetic susceptibility Hikurangi subduction margin IODP Expedition 375 soft sediment deformation strain partitioning
英文关键词	Deformation; Faulting; Magnetic anisotropy; Magnetic susceptibility; Magnetism; Sediments; Structural geology; Textures; Anisotropy of magnetic susceptibility; Axial orientations; Convergence directions; Gravitational loading; Hanging-wall sequences; Hikurangi subduction margins; Strain partitioning; Texture development; Strain; accretion; deformation; fault zone; footwall; hanging wall; magnetic anisotropy; spatial distribution; strain analysis; strain partitioning; subduction zone; thrust fault; Hikurangi Margin; New Zealand; Pacific Ocean
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202618
作者单位	Institute for Marine-Earth Exploration and Engineering, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan; Center for Advanced Marine Core Research, Kochi University, Nankoku, Japan; Geophysical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany; Institute of Geosciences and Geography, Martin-Luther University, Halle, Germany; Department of Global Environment and Disaster Prevention, Faculty of Science and Technology, Kochi University, Japan
推荐引用方式 GB/T 7714	Greve A.,Kars M.,Zerbst L.,et al. Strain partitioning across a subduction thrust fault near the deformation front of the Hikurangi subduction margin, New Zealand: A magnetic fabric study on IODP Expedition 375 Site U1518[J],2020,542.
APA	Greve A.,Kars M.,Zerbst L.,Stipp M.,&Hashimoto Y..(2020).Strain partitioning across a subduction thrust fault near the deformation front of the Hikurangi subduction margin, New Zealand: A magnetic fabric study on IODP Expedition 375 Site U1518.Earth and Planetary Science Letters,542.
MLA	Greve A.,et al."Strain partitioning across a subduction thrust fault near the deformation front of the Hikurangi subduction margin, New Zealand: A magnetic fabric study on IODP Expedition 375 Site U1518".Earth and Planetary Science Letters 542(2020).