气候变化领域集成服务门户(CCPortal): Characterizing the Influence of Fracture Density on Network Scale Transport

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DOI	10.1029/2019JB018547
	Characterizing the Influence of Fracture Density on Network Scale Transport
	Sherman T.; Hyman J.; Dentz M.; Bolster D.
发表日期	2020
ISSN	21699313
卷号	125 期号:1
英文摘要	The topology of natural fracture networks is inherently linked to the structure of the fluid velocity field and transport therein. Here we study the impact of network density on flow and transport behaviors. We stochastically generate fracture networks of varying density and simulate flow and transport with a discrete fracture network model, which fully resolves network topology at the fracture scale. We study conservative solute trajectories with Lagrangian particle tracking and find that as fracture density decreases, solute channelization to large local fractures increases, thereby reducing plume spreading. Furthermore, in sparse networks mean particle travel distance increases and local network features, such as velocity zones where flow is counter to the primary pressure gradient, become increasingly important for transport. As the network density increases, network statistics homogenize and such local features have a reduced impact. We quantify local topological influence on transport behavior with an effective tortuosity parameter, which measures the ratio of total advective distance to linear distance at the fracture scale; large tortuosity values are correlated to slow-velocity regions. These large tortuosity, slow-velocity regions delay downstream transport and enhance tailing on particle breakthrough curves. Finally, we predict transport with an upscaled, Bernoulli spatial Markov random walk model and parameterize local topological influences with a novel tortuosity parameter. Bernoulli model predictions improve when sampling from a tortuosity distribution, as opposed to a fixed value as has previously been done, suggesting that local network topological features must be carefully considered in upscaled modeling efforts of fracture network systems. ©2019. American Geophysical Union. All Rights Reserved.
英文关键词	CTRW; DFN; fracture networks; transport
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/188021
作者单位	Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN, United States; Computational Earth Science Group(EES-16), Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM, United States; Spanish National Research Council (IDAEA-CSIC), Barcelona, Spain
推荐引用方式 GB/T 7714	Sherman T.,Hyman J.,Dentz M.,et al. Characterizing the Influence of Fracture Density on Network Scale Transport[J],2020,125(1).
APA	Sherman T.,Hyman J.,Dentz M.,&Bolster D..(2020).Characterizing the Influence of Fracture Density on Network Scale Transport.Journal of Geophysical Research: Solid Earth,125(1).
MLA	Sherman T.,et al."Characterizing the Influence of Fracture Density on Network Scale Transport".Journal of Geophysical Research: Solid Earth 125.1(2020).