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Title: Evaluating the effect of internal aperture variability on transport in kilometer scale discrete fracture networks

Journal Article · · Advances in Water Resources
 [1];  [1];  [1];  [2];  [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

The apertures of natural fractures in fractured rock are highly heterogeneous. However, in-fracture aperture variability is often neglected in flow and transport modeling and individual fractures are assumed to have uniform aperture distribution. The relative importance of in-fracture variability in flow and transport modeling within kilometer-scale fracture networks has been under debate for a long time, since the flow in each single fracture is controlled not only by in-fracture variability but also by boundary conditions. Computational limitations have previously prohibited researchers from investigating the relative importance of in-fracture variability in flow and transport modeling within large-scale fracture networks. We address this question by incorporating internal heterogeneity of individual fractures into flow simulations within kilometer scale three-dimensional fracture networks, where fracture intensity, P32 (ratio between total fracture area and domain volume) is between 0.027 and 0.031 [1/m]. The recently developed discrete fracture network (DFN) simulation capability, dfnWorks, is used to generate kilometer scale DFNs that include in-fracture aperture variability represented by a stationary log-normal stochastic field with various correlation lengths and variances. The Lagrangian transport parameters, non-reacting travel time, , and cumulative retention, , are calculated along particles streamlines. As a result, it is observed that due to local flow channeling early particle travel times are more sensitive to in-fracture aperture variability than the tails of travel time distributions, where no significant effect of the in-fracture aperture variations and spatial correlation length is observed.

Research Organization:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Fossil Energy (FE), Oil & Natural Gas
Grant/Contract Number:
AC52-06NA25396; AC05-00OR22725
OSTI ID:
1260532
Alternate ID(s):
OSTI ID: 1261554; OSTI ID: 1325331
Report Number(s):
LA-UR-15-29340
Journal Information:
Advances in Water Resources, Vol. 94; ISSN 0309-1708
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 69 works
Citation information provided by
Web of Science

References (36)

Analysis and Visualization of Discrete Fracture Networks Using a Flow Topology Graph journal August 2017
Physical pictures of transport in heterogeneous media: Advection-dispersion, random-walk, and fractional derivative formulations: TRANSPORT IN HETEROGENEOUS MEDIA journal October 2002
Scaling of fracture systems in geological media journal August 2001
Hydrodynamic control of tracer retention in heterogeneous rock fractures: HYDRODYNAMIC CONTROL OF RETENTION IN FRACTURES journal May 2003
Solute transport and retention in three-dimensional fracture networks: TRANSPORT IN FRACTURE NETWORKS journal February 2012
Transport of reactive tracers in rock fractures journal January 1999
Stochastic simulation of radionuclide migration in discretely fractured rock near the Äspö Hard Rock Laboratory: RETENTION IN FRACTURE NETWORKS journal February 2004
Time behavior of solute transport in heterogeneous media: transition from anomalous to normal transport journal February 2004
Derivation of equivalent pipe network analogues for three-dimensional discrete fracture networks by the boundary element method journal September 1999
Influence of fracture scale heterogeneity on the flow properties of three-dimensional discrete fracture networks (DFN): 3D FRACTURE NETWORK PERMEABILITY journal November 2012
Significance of injection modes and heterogeneity on spatial and temporal dispersion of advecting particles in two-dimensional discrete fracture networks journal May 2009
Stochastic subsurface hydrology from theory to applications journal August 1986
Approaches and algorithms for groundwater flow modeling in support of site investigations and safety assessment of the Forsmark site, Sweden journal September 2013
Conforming Delaunay Triangulation of Stochastically Generated Three Dimensional Discrete Fracture Networks: A Feature Rejection Algorithm for Meshing Strategy journal January 2014
Fracture size and transmissivity correlations: Implications for transport simulations in sparse three-dimensional discrete fracture networks following a truncated power law distribution of fracture size: FRACTURE SIZE AND TRANSMISSIVITY CORRELATIONS journal August 2016
dfnWorks: A discrete fracture network framework for modeling subsurface flow and transport journal November 2015
Influence of injection mode on transport properties in kilometer-scale three-dimensional discrete fracture networks: INFLUENCE OF INJECTION MODE IN 3-D DFNs journal September 2015
Effect of fracture aperture variations on the dispersion of contaminants journal January 1999
A study of flow-wetted surface area in a single fracture as a function of its hydraulic conductivity distribution: FLOW-WETTED SURFACE FOR HETEROGENEOUS FRACTURES journal January 2012
A new approach to account for fracture aperture variability when modeling solute transport in fracture networks: A NEW APPROACH IN FRACTURE NETWORK MODELS journal April 2013
Particle tracking approach for transport in three-dimensional discrete fracture networks: Particle tracking in 3-D DFNs journal September 2015
Analysis of Some Laboratory Tracer Runs in Natural Fissures journal July 1985
Flow and tracer transport in a single fracture: A stochastic model and its relation to some field observations journal December 1988
Flow channeling in strongly heterogeneous porous media: A numerical study journal May 1994
Trends, prospects and challenges in quantifying flow and transport through fractured rocks journal February 2005
A variable aperture fracture network model for flow and transport in fractured rocks journal June 1992
Stochastic analysis of early tracer arrival in a segmented fracture pathway journal June 2001
Transport and retention in fractured rock: Consequences of a power-law distribution for fracture lengths journal June 1998
Power-law velocity distributions in fracture networks: Numerical evidence and implications for tracer transport: POWER-LAW VELOCITY DISTRIBUTIONS IN FRACTURE NETWORKS journal July 2002
Upscaling discrete fracture network simulations: An alternative to continuum transport models: UPSCALING FRACTURE NETWORK SIMULATIONS journal February 2005
Pathline tracing on fully unstructured control-volume grids journal July 2012
Multivariable geostatistics in S: the gstat package journal August 2004
Gstat: a program for geostatistical modelling, prediction and simulation journal January 1998
Channel model of flow through fractured media journal March 1987
Flow channeling in a single fracture as a two-dimensional strongly heterogeneous permeable medium journal September 1989
Simulation of the von mises fisher distribution journal January 1994

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Statistical Formulation of Generalized Tracer Retention in Fractured Rock: TRACER RETENTION IN FRACTURED ROCK journal November 2017
Characterizing the Impact of Fractured Caprock Heterogeneity on Supercritical CO$$_2$$ Injection journal November 2019
Advective Transport in Discrete Fracture Networks With Connected and Disconnected Textures Representing Internal Aperture Variability journal July 2019
Quantifying Topological Uncertainty in Fractured Systems using Graph Theory and Machine Learning journal August 2018
Digital Rock Approach to Model the Permeability in an Artificially Heated and Fractured Granodiorite from the Liquiñe Geothermal System (39°S) journal September 2019
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