气候变化领域集成服务门户(CCPortal): Coupled Evolution of Deformation, Pore Fluid Pressure, and Fluid Flow in Shallow Subduction Forearcs

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DOI	10.1029/2019JB019101
	Coupled Evolution of Deformation, Pore Fluid Pressure, and Fluid Flow in Shallow Subduction Forearcs
	Sun T.; Ellis S.; Saffer D.
发表日期	2020
ISSN	21699313
卷号	125 期号:3
英文摘要	Deformation and fluid flow in subduction zone forearcs are dynamically coupled, but our quantitative understanding of their coupling is incomplete. In this work, we investigate the hydrological and mechanical coupling in shallow forearcs, using a Lagrangian-Eulerian finite element model that incorporates constitutive and transport properties of sediments and faults constrained by laboratory and field measurements. Wide-ranging observations show that sediment thickness and composition, plate convergence rate, basement strength and roughness, and subducting slab dip angle vary between subduction zones. We therefore systematically study their effects on forearc stress and pore fluid pressure states, consolidation and dewatering patterns, and margin morphology. Our models, with the incorporation of a simple description of permeability enhancement along fault damage zones, yield a range of fault permeability (10−13–10−17 m2) consistent with previous estimates and describe the important role of upper plate splay faults in causing heterogeneous dewatering and consolidation patterns and in modulating effective normal stress on the plate interface. Spatial variations in tectonic loading and sediment consolidation can also be caused by subducting basement roughness such as a horst-and-graben structure. For typically observed relief and spacing, our models predict locally enhanced porosity reduction by up to 50% at the downdip edge of the horsts and anomalously high sediment porosity above the geometrical highs. At the margin scale, our results demonstrate that sediment permeability and thickness are dominant controls on fluid overpressure, sediment compaction, and megathrust strength. Rough and frictionally strong megathrusts produce similar effects in driving high wedge tapers. ©2020 Her Majesty the Queen in Right of Canada, as represented by the Minister of Natural Resources
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187892
作者单位	Department of Geosciences, Pennsylvania State University, University ParkPA, United States; Now at Pacific Geoscience Centre, Geological Survey of Canada, Natural Resources Canada, Sidney, BC, Canada; Department of Earth Structure and Processes, GNS Science, Lower Hutt, New Zealand; University of Texas Institute for Geophysics, Austin, TX, United States; Department of Geological Sciences, Jackson School of Geosciences, Austin, TX, United States
推荐引用方式 GB/T 7714	Sun T.,Ellis S.,Saffer D.. Coupled Evolution of Deformation, Pore Fluid Pressure, and Fluid Flow in Shallow Subduction Forearcs[J],2020,125(3).
APA	Sun T.,Ellis S.,&Saffer D..(2020).Coupled Evolution of Deformation, Pore Fluid Pressure, and Fluid Flow in Shallow Subduction Forearcs.Journal of Geophysical Research: Solid Earth,125(3).
MLA	Sun T.,et al."Coupled Evolution of Deformation, Pore Fluid Pressure, and Fluid Flow in Shallow Subduction Forearcs".Journal of Geophysical Research: Solid Earth 125.3(2020).