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| Titel |
Determination of hydraulic equivalents for layers of fractured sedimentary rock: Method and application to borehole data from the Hunter Valley, Australia |
| VerfasserIn |
Xiang-Zhao Kong, Detlef Bringemeier, Sergio Galindo-Torres, Alexander Scheuermann, Martin Saar, Ling Li |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250102059
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| Publikation (Nr.) |
 EGU/EGU2015-1338.pdf |
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| Zusammenfassung |
| Whether a fractured, especially multi-layered and multi-lithological, rock mass can be
approximated by an equivalent continuum model has long been an important question for
studies of fluid flow through this complex porous medium. Here we introduce a numerical
procedure to evaluate the hydraulic equivalents, e.g., permeability tensor of fractured
sedimentary rock layers, using a stochastic Representative Elementary Volume (REV)
approach based on borehole data obtained during site investigations in the Hunter Valley,
NSW, Australia Multiple realizations of stochastic, three-dimensional (3D) Discrete Fracture
Network (DFN) models are generated, using Monte-Carlo simulations of fractured
sedimentary rock layers, that are based on statistically derived fracture and lithological input
data from borehole geological samples and geophysical logs. In order to determine an
appropriate REV size, sub fracture systems with varying cubic model sizes, from
0.253 m3 to 103 m3, were extracted
from the stochastically generated DFN models and evaluated for their equivalent
permeability tensors. Results from the Monte-Carlo simulations corroborate that
an REV exists and demonstrate that the variance of the calculated permeability
values decreases significantly as the size of the extracted DFN model increases.
Analysis shows that the coefficient of variation (the ratio of standard deviation
over the mean value) of the diagonal permeability values decrease sharply from
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