气候变化领域集成服务门户(CCPortal): Pore Fluid Pressures and Strength Contrasts Maintain Frontal Fault Activity; Northern Hikurangi Margin; New Zealand

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DOI	10.1029/2020GL089209
	Pore Fluid Pressures and Strength Contrasts Maintain Frontal Fault Activity; Northern Hikurangi Margin; New Zealand
	French M.E.; Morgan J.K.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:21
英文摘要	Diverse modes of fault slip occur within shallow subduction zones, but their relationships to upper plate deformation are poorly understood. IODP Expedition 375 collected samples and data across the northern Hikurangi margin, where tsunamigenic earthquakes and slow slip events occur. Site U1518 intersected the Pāpaku fault, a splay fault within the frontal accretionary wedge. To constrain in situ physical conditions and strength of the system, we conducted isotropic loading and triaxial compression experiments on hanging wall and foot wall cores and interpreted the results using critical state soil mechanics theory. The hanging wall is relatively strong, reflecting its tectonic history, whereas the foot wall and fault are anomalously weak owing to elevated pore pressure (λ∗ ≥ 0.3). Critical state in both samples corresponds to a friction coefficient of 0.6, constraining the strength of the Pāpaku fault. Low fault strength, maintained by excess pore pressures, suggests that the Pāpaku fault may still be active. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Critical current density (superconductivity); Fault slips; Friction; Pore pressure; Soil mechanics; Accretionary wedge; Critical state soil mechanics theory; Excess pore pressure; Friction coefficients; Isotropic loading; Physical conditions; Pore fluid pressure; Triaxial compression; Structural geology; accretion; critical state; deformation mechanism; earthquake event; fault slip; hanging wall; pore pressure; soil mechanics; subduction zone; Hikurangi Margin; New Zealand; Pacific Ocean
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/169527
作者单位	Department of Earth, Environmental, and Planetary Sciences, Rice University, Houston, TX, United States
推荐引用方式 GB/T 7714	French M.E.,Morgan J.K.. Pore Fluid Pressures and Strength Contrasts Maintain Frontal Fault Activity; Northern Hikurangi Margin; New Zealand[J],2020,47(21).
APA	French M.E.,&Morgan J.K..(2020).Pore Fluid Pressures and Strength Contrasts Maintain Frontal Fault Activity; Northern Hikurangi Margin; New Zealand.Geophysical Research Letters,47(21).
MLA	French M.E.,et al."Pore Fluid Pressures and Strength Contrasts Maintain Frontal Fault Activity; Northern Hikurangi Margin; New Zealand".Geophysical Research Letters 47.21(2020).