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Title: Effective transmissivity of two-dimensional fracture networks

Abstract

Many of the sites that have been proposed as potential locations of underground radioactive waste repositories contain fractured rocks. For example, both the saturated and unsaturated zone at Yucca Mountain, Nevada, contains many hydrogeologic units that are extensively fractured. When modeling the hydrological behavior of these sites, for either the purpose of site characterization of performance assessment, computational grid-blocks are often used that contain large number of fractures. In order to treat these as equivalent continua, it is necessary to develop a procedure for relating the hydraulic properties of the individual fractures and he topology of the fracture network to the overall scale permeability. One aspect of this problem is that of determining the in situ hydraulic properties of the individual fractures. Another aspect is to reconstruct the three-dimensional geometry of the fracture network based on borehole or outcrop measurements. The final stage in the problem is that of taking a network of known geometry and determining it effective scale conductivity. The purpose of this paper is to describe a simple procedure for solving this latter problem,a nd to demonstrate it use in cases of both saturated and unsaturated flow. The TOUGH simulator was used.

Authors:
;
Publication Date:
Research Org.:
Lawrence Berkeley Lab., CA (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
87080
Report Number(s):
LBL-37332
ON: DE95015139; TRN: 95:017375
DOE Contract Number:
AC03-76SF00098
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Apr 1995
Country of Publication:
United States
Language:
English
Subject:
05 NUCLEAR FUELS; 54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; HIGH-LEVEL RADIOACTIVE WASTES; UNDERGROUND DISPOSAL; ROCKS; HYDRAULIC CONDUCTIVITY; HYDROLOGY; T CODES; HYDRAULIC FRACTURES; COMPUTERIZED SIMULATION; YUCCA MOUNTAIN; Yucca Mountain Project

Citation Formats

Zimmerman, R.W., and Bodvarsson, G.S.. Effective transmissivity of two-dimensional fracture networks. United States: N. p., 1995. Web. doi:10.2172/87080.
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Zimmerman, R.W., & Bodvarsson, G.S.. Effective transmissivity of two-dimensional fracture networks. United States. doi:10.2172/87080.
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Zimmerman, R.W., and Bodvarsson, G.S.. Sat . "Effective transmissivity of two-dimensional fracture networks". United States. doi:10.2172/87080. https://www.osti.gov/servlets/purl/87080.
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@article{osti_87080,
title = {Effective transmissivity of two-dimensional fracture networks},
author = {Zimmerman, R.W. and Bodvarsson, G.S.},
abstractNote = {Many of the sites that have been proposed as potential locations of underground radioactive waste repositories contain fractured rocks. For example, both the saturated and unsaturated zone at Yucca Mountain, Nevada, contains many hydrogeologic units that are extensively fractured. When modeling the hydrological behavior of these sites, for either the purpose of site characterization of performance assessment, computational grid-blocks are often used that contain large number of fractures. In order to treat these as equivalent continua, it is necessary to develop a procedure for relating the hydraulic properties of the individual fractures and he topology of the fracture network to the overall scale permeability. One aspect of this problem is that of determining the in situ hydraulic properties of the individual fractures. Another aspect is to reconstruct the three-dimensional geometry of the fracture network based on borehole or outcrop measurements. The final stage in the problem is that of taking a network of known geometry and determining it effective scale conductivity. The purpose of this paper is to describe a simple procedure for solving this latter problem,a nd to demonstrate it use in cases of both saturated and unsaturated flow. The TOUGH simulator was used.},
doi = {10.2172/87080},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 1995},
month = {Sat Apr 01 00:00:00 EST 1995}
}
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DOI:  10.2172/87080
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