Size effect on aperture and permeability of a fracture as estimated in large synthetic fractures

Matsuki, Koji; Chida, Yusuke; Sakaguchi, Kiyotoshi; Glover, Paul

doi:10.1016/j.ijrmms.2005.12.001

Cited by 109 publications

(140 citation statements)

References 25 publications

Supporting

Mentioning

124

Contrasting

Unclassified

Order By: Relevance

“…One of the main difficulties is to correctly take into account the increasing influence of the contact area as the fracture aperture is decreased [8][9][10][11]. We analyze in this Letter the dispersion problem at finite Péclet number and identify the proper aperture measure for this problem, taking into account severe heterogeneities such as large contact zones.…”

mentioning

confidence: 99%

Relation between first arrival time and permeability in self-affine fractures with areas in contact

Talon¹,

Auradou²,

Hansen³

2012

EPL

View full text Add to dashboard Cite

-We demonstrate that the first arrival time in dispersive processes in self-affine fractures are governed by the same length scale characterizing the fractures as that which controls their permeability. In one-dimensional channel flow this length scale is the aperture of the bottle neck, i.e., the region having the smallest aperture. In two dimensions, the concept of a bottle neck is generalized to that of a minimal path normal to the flow. The length scale is then the average aperture along this path. There is a linear relationship between the first arrival time and this length scale, even when there is strong overlap between the fracture surfaces creating areas with zero permeability. We express the first arrival time directly in terms of the permeability.Due to their role in the flow properties of tight and low permeability reservoirs such as shale gas reservoirs and carbonate reservoirs, and on contaminant transport e.g. in connection with waste storage, the study of transport in fractures is still a very vigorous field [1][2][3][4]. Most present theoretical efforts attempts to relate the transport properties of fractures to the statistics of the aperture fields through analytical models based on statistical averages, weak disorder perturbation expansions [5], mean-field approximations or simplified aperture models [6]. We also mention the work of Zhan and Yortsos [7] where a method to deduce the heterogenities of a permeability distribution from the concentration arrival time field was proposed.Due to the surface roughness, i.e., the heterogenities of the aperture field, these relations provide satisfactory results only over a finite range of conditions and do not permit to predict the behavior of a fracture with large heterogenities in aperture field. One of the main difficulties is to correctly take into account the increasing influence of the contact area as the fracture aperture is decreased [8][9][10][11]. We analyze in this Letter the dispersion problem at finite Péclet number and identify the proper aperture measure for this problem, taking into account severe heterogeneities such as large contact zones. Our main focus is on the breakthrough time, i.e., the time at which the tracer appears at a given position. The p-1

show abstract

mentioning

confidence: 99%

Relation between first arrival time and permeability in self-affine fractures with areas in contact

Talon¹,

Auradou²,

Hansen³

2012

EPL

View full text Add to dashboard Cite

show abstract

“…As funções de distribuição de abertura fornecem a probabilidade que pontos com certa abertura ocorram no plano da fratura. As distribuições contínuas do tipo normal (Oron e Berkowitz, 1998;Matsuki et al, 2006;Schmittbuhl et al, 2008;Neuville et al, 2012) e lognormal (Moreno e Tsang, 1994;Zimmerman e Bodvarsson, 1996;Keller, 1998;Nowamooz et al, 2013) têm sido os mais adequados.…”

Section: Lista De Figurasunclassified

“…As distribuições de probabilidade contínuas do tipo normal (Matsuki et al, 2006;Vickers et al, 1992;Yeo et al, 1998;Schmittbuhl et al, 2008;Neuville et al, 2012; Oron e Berkowitz, 1998) e lognormal (Figura 10) (Moreno e Tsang, 1994;Zimmerman e Bodvarsson, 1996;Pyrak-Nolte et al, 1997;Keller, 1998;Wendland e Himmelsbach, 2002;Zheng et al, 2008;Nowamooz et al, 2013;Wang e Cardenas, 2014;Ishibashi et al, 2015) têm sido as mais adequadas nos trabalhos científicos.…”

Section: Abertura Variável: Simulação Estocástica Sequencialunclassified

“…O valor do expoente de Hurst reportado para materiais como o cimento e o granito é =0,8 (Brown, 1989;Måløy et al, 1992;Poon et al, 1992;Auradou et al, 2005;Matsuki et al, 2006) e =0,5 para arenitos (Boffa et al, 1998;Ponson et al, 2007). No entanto, a estimativa 0,75 < ≤ 0,8, também foi reportada para arenitos (Nasseri et al, 2006).…”

Section: Abertura Variável: Simulação Estocástica Fractalunclassified

“…Nessas situações, o conceito de abertura de fratura tornase questionável (Gouze et al, 2003). Para simplificação do campo de abertura, esses pixels foram contabilizados como pontos de contato entre as paredes da fratura, isto é, As distribuições do tipo normal (Matsuki et al, 2006;Vickers et al, 1992;Yeo et al, 1998;Schmittbuhl et al, 2008;Neuville et al, 2012;Oron e Berkowitz, 1998) e lognormal têm sido as mais utilizadas nos estudos sobre fraturas em escala de laboratório (Moreno e Tsang, 1994;Zimmerman e Bodvarsson, 1996;Pyrak-Nolte et al, 1997;Keller, 1998;Wendland e Himmelsbach, 2002;Zheng et al, 2008;Nowamooz et al, 2013;Wang e Cardenas, 2014;Ishibashi et al, 2015). O resultado das "aberturas equivalentes" mostrou que a abertura de balanço de massa (bm) foi maior em relação à abertura hidráulica (bc), a qual foi maior que a abertura de perda por atrito (bl) (Tabela 2).…”

Section: Abertura Da Fraturaunclassified

See 2 more Smart Citations

Migração de solutos em basalto fraturado: quantificação experimental em laboratório e validação matemática

Lucas¹

View full text Add to dashboard Cite

A avaliação do risco a contaminação e a escolha de técnicas de remediação de poluentes em aquíferos fraturados depende da quantificação dos fenômenos envolvidos no transporte de solutos. A geometria da fratura, usualmente caracterizada pela abertura, é o principal parâmetro que indiretamente controla o transporte nos aquíferos fraturados. A simplificação mais comum desse problema é assumir que as fraturas são um par de placas planas e paralelas, isto é, com uma abertura constante. No entanto, por causa do limitado número de trabalhos experimentais, não está esclarecida a adequabilidade do uso de uma abertura constante para simular o transporte conservativo em fraturas do Aquífero Serra Geral (ASG), Brasil. O objetivo deste trabalho é avaliar a influência da abertura de uma fratura natural do Aquífero Serra Geral sob o transporte conservativo de solutos. Uma amostra natural de basalto fraturado foi usada em um experimento hidráulico e de transporte de um traçador conservativo (escala de laboratório). O campo de abertura foi medido usando a técnica avançada, de alta resolução e tridimensional, chamada microtomografia computadorizada de raios-X. A concentração de traçador medida foi utilizada para validar uma solução analítica unidimensional da Equação de Advecção-dispersão (ADE). O desemprenho do ajuste da ADE às curvas de passagem experimentais foi avaliado para quatro diferentes tipos de aberturas constantes. Os resultados mostraram que o escoamento de água e o transporte de contaminantes pode ocorrer através de fraturas micrométricas, ocasionando, eventualmente, a contaminação do ASG. A abertura de balanço de massa é a única que pode ser chamada propriamente de "abertura equivalente". O uso de aberturas constantes na ADE não permitiu representar completamente o formato das curvas de passagem porque o campo de velocidade não é uniforme e intrinsicamente bidimensional. Portanto, na simulação do transporte deve-se incorporar a heterogeneidade da abertura da fratura.Palavras-chave: Advecção-dispersão, Breakthrough curve, Espectrofotometria, Lei Cúbica, Microtomografia de raios-X. The contamination risk assessment and the choice of suitable cleanup techniques for pollutants in fractured rock depends on the quantification of the transport phenomena. Fracture geometry often described by the apertures is the major parameter that controls indirectly solute transport in fractured rock. The simplest approach is describing fractures as a pair of smooth parallel plates with constant aperture. However, there is a lack of information about the suitability for using a constant aperture for the conservative solute transport prediction in a single fracture of Serra Geral Aquifer (SGA), Brazil. The aim of this work is to evaluate the effect of aperture variability in a natural single rough-walled fracture of Serra Geral Aquifer on conservative solute transport. A natural core of fractured basalt was used for a hydraulic and tracer tests (laboratory scale). The aperture field was measured using the advanced, high-resolution and tr...

show abstract

Critical Reynolds number for nonlinear flow through rough-walled fractures: The role of shear processes

et al. 2014

View full text Add to dashboard Cite

This paper experimentally investigates the role of shear processes on the variation of critical Reynolds number and nonlinear flow through rough-walled rock fractures. A quantitative criterion was developed to quantify the onset of nonlinear flow by comprehensive combination of Forchheimer's law and Reynolds number. At each shear displacement, several high-precision water flow tests were carried out with different hydraulic gradients then the critical Reynolds number was determined based on the developed criterion. The results show that (i) the Forchheimer's law was fitted very well to experimental results of nonlinear fluid flow through rough-walled fractures, (ii) the coefficients of viscous and inertial pressure drops experience 4 and 7 orders of magnitude reduction during shear displacement, respectively, and (iii) the critical Reynolds number varies from 0.001 to 25 and experiences 4 orders of magnitude enlargement by increasing shear displacement from 0 to 20 mm. These findings may prove useful in proper understanding of fluid flow through rock fractures, or inclusions in computational studies of large-scale nonlinear flow in fractured rocks.

show abstract

Size effect on aperture and permeability of a fracture as estimated in large synthetic fractures

Cited by 109 publications

References 25 publications

Relation between first arrival time and permeability in self-affine fractures with areas in contact

Relation between first arrival time and permeability in self-affine fractures with areas in contact

Migração de solutos em basalto fraturado: quantificação experimental em laboratório e validação matemática

Critical Reynolds number for nonlinear flow through rough-walled fractures: The role of shear processes

Contact Info

Product

Resources

About