KG²B, a collaborative benchmarking exercise ...
Document type :
Article dans une revue scientifique
DOI :
Permalink :
Title :
KG²B, a collaborative benchmarking exercise for estimating the permeability of the Grimsel granodiorite – Part 1: measurements, pressure dependence and pore-fluid effects
Author(s) :
David, C. [Auteur]
Wassermann, J [Auteur]
Amann, F [Auteur]
Lockner, D A [Auteur]
Rutter, E H [Auteur]
Vanorio, T [Auteur]
Amann Hildenbrand, A [Auteur]
Billiotte, J [Auteur]
Reuschlé, T [Auteur]
Lasseux, D [Auteur]
Fortin, J [Auteur]
Lenormand, R [Auteur]
Selvadurai, A P S [Auteur]
Meredith, P G [Auteur]
Browning, J [Auteur]
Mitchell, T M [Auteur]
Loggia, D [Auteur]
Nono, F [Auteur]
Sarout, J [Auteur]
Esteban, L [Auteur]
Davy, Catherine [Auteur]
Centrale Lille
Louis, L [Auteur]
Boitnott, G [Auteur]
Madonna, C [Auteur]
Jahns, E [Auteur]
Fleury, M [Auteur]
Berthe, G [Auteur]
Delage, P [Auteur]
Braun, P [Auteur]
Grégoire, D [Auteur]
Perrier, L [Auteur]
Polito, P [Auteur]
Jannot, Y [Auteur]
Sommier, A [Auteur]
Krooss, B [Auteur]
Fink, R [Auteur]
Hu, Q [Auteur]
Klaver, J [Auteur]
Clark, A [Auteur]
Wassermann, J [Auteur]
Amann, F [Auteur]
Lockner, D A [Auteur]
Rutter, E H [Auteur]
Vanorio, T [Auteur]
Amann Hildenbrand, A [Auteur]
Billiotte, J [Auteur]
Reuschlé, T [Auteur]
Lasseux, D [Auteur]
Fortin, J [Auteur]
Lenormand, R [Auteur]
Selvadurai, A P S [Auteur]
Meredith, P G [Auteur]
Browning, J [Auteur]
Mitchell, T M [Auteur]
Loggia, D [Auteur]
Nono, F [Auteur]
Sarout, J [Auteur]
Esteban, L [Auteur]
Davy, Catherine [Auteur]
Centrale Lille
Louis, L [Auteur]
Boitnott, G [Auteur]
Madonna, C [Auteur]
Jahns, E [Auteur]
Fleury, M [Auteur]
Berthe, G [Auteur]
Delage, P [Auteur]
Braun, P [Auteur]
Grégoire, D [Auteur]
Perrier, L [Auteur]
Polito, P [Auteur]
Jannot, Y [Auteur]
Sommier, A [Auteur]
Krooss, B [Auteur]
Fink, R [Auteur]
Hu, Q [Auteur]
Klaver, J [Auteur]
Clark, A [Auteur]
Journal title :
Geophysical Journal International
Volume number :
215
Pages :
799-824
Publisher :
Oxford University Press (OUP)
Publication date :
2018-11
English keyword(s) :
Permeability and porosity
Microstructure
Hydrogeophysics
Microstructure
Hydrogeophysics
HAL domain(s) :
Chimie/Matériaux
English abstract : [en]
Measuring the permeability of tight rocks remains a challenging task. In addition to the traditional sources of errors that affect more permeable formations (e.g. sample selection, non-representative specimens, disturbance ...
Show more >Measuring the permeability of tight rocks remains a challenging task. In addition to the traditional sources of errors that affect more permeable formations (e.g. sample selection, non-representative specimens, disturbance introduced during sample acquisition and preparation), tight rocks can be particularly prone to solid–fluid interactions and thus more sensitive to the methods, procedures and techniques used to measure permeability. To address this problem, it is desirable to collect, for a single material, measurements obtained by different methods and pore-fluids. For that purpose a collaborative benchmarking exercise involving 24 laboratories was organized for measuring the permeability of a single low permeability material, the Grimsel granodiorite, at a common effective confining pressure (5 MPa). The objectives of the benchmark were: (i) to compare the results for a given method, (ii) to compare the results between different methods, (iii) to analyze the accuracy of each method, (iv) to study the influence of experimental conditions (especially the nature of pore fluid), (v) to discuss the relevance of indirect methods and models and finally (vi) to suggest good practice for low permeability measurements. In total 39 measurements were collected that allowed us to discuss the influence of (i) pore-fluid, (ii) measurement method, (iii) sample size and (iv) pressure sensitivity. Discarding some outliers from the bulk data set (4 out of 39) an average permeability of 1.11 × 10−18 m² with a standard deviation of 0.57 × 10−18 m² was obtained. The most striking result was the large difference in permeability for gas measurements compared to liquid measurements. Regardless of the method used, gas permeability was higher than liquid permeability by a factor approximately 2 (kgas = 1.28 × 10−18 m² compared to kliquid = 0.65 × 10−18 m²). Possible explanations are that (i) liquid permeability was underestimated due to fluid-rock interactions (ii) gas permeability was overestimated due to insufficient correction for gas slippage and/or (iii) gases and liquids do not probe exactly the same porous networks. The analysis of Knudsen numbers shows that the gas permeability measurements were performed in conditions for which the Klinkenberg correction is sufficient. Smaller samples had a larger scatter of permeability values, suggesting that their volume were below the Representative Elementary Volume. The pressure dependence of permeability was studied by some of the participating teams in the range 1–30 MPa and could be fitted to an exponential law k = ko.exp(–γPeff) with γ = 0.093 MPa−1. Good practice rules for measuring permeability in tight materials are also provided.Show less >
Show more >Measuring the permeability of tight rocks remains a challenging task. In addition to the traditional sources of errors that affect more permeable formations (e.g. sample selection, non-representative specimens, disturbance introduced during sample acquisition and preparation), tight rocks can be particularly prone to solid–fluid interactions and thus more sensitive to the methods, procedures and techniques used to measure permeability. To address this problem, it is desirable to collect, for a single material, measurements obtained by different methods and pore-fluids. For that purpose a collaborative benchmarking exercise involving 24 laboratories was organized for measuring the permeability of a single low permeability material, the Grimsel granodiorite, at a common effective confining pressure (5 MPa). The objectives of the benchmark were: (i) to compare the results for a given method, (ii) to compare the results between different methods, (iii) to analyze the accuracy of each method, (iv) to study the influence of experimental conditions (especially the nature of pore fluid), (v) to discuss the relevance of indirect methods and models and finally (vi) to suggest good practice for low permeability measurements. In total 39 measurements were collected that allowed us to discuss the influence of (i) pore-fluid, (ii) measurement method, (iii) sample size and (iv) pressure sensitivity. Discarding some outliers from the bulk data set (4 out of 39) an average permeability of 1.11 × 10−18 m² with a standard deviation of 0.57 × 10−18 m² was obtained. The most striking result was the large difference in permeability for gas measurements compared to liquid measurements. Regardless of the method used, gas permeability was higher than liquid permeability by a factor approximately 2 (kgas = 1.28 × 10−18 m² compared to kliquid = 0.65 × 10−18 m²). Possible explanations are that (i) liquid permeability was underestimated due to fluid-rock interactions (ii) gas permeability was overestimated due to insufficient correction for gas slippage and/or (iii) gases and liquids do not probe exactly the same porous networks. The analysis of Knudsen numbers shows that the gas permeability measurements were performed in conditions for which the Klinkenberg correction is sufficient. Smaller samples had a larger scatter of permeability values, suggesting that their volume were below the Representative Elementary Volume. The pressure dependence of permeability was studied by some of the participating teams in the range 1–30 MPa and could be fitted to an exponential law k = ko.exp(–γPeff) with γ = 0.093 MPa−1. Good practice rules for measuring permeability in tight materials are also provided.Show less >
Language :
Anglais
Peer reviewed article :
Oui
Audience :
Internationale
Popular science :
Non
Administrative institution(s) :
ENSCL
CNRS
Centrale Lille
Univ. Artois
Université de Lille
CNRS
Centrale Lille
Univ. Artois
Université de Lille
Collections :
Research team(s) :
Chimie, matériaux et procédés pour un nucléaire durable (CIMEND)
Submission date :
2019-09-25T15:06:58Z
2021-03-04T11:18:47Z
2021-03-04T11:18:47Z