The Experts below are selected from a list of 6933 Experts worldwide ranked by ideXlab platform
Frédéric Skoczylas - One of the best experts on this subject based on the ideXlab platform.
-
research on Gas Migration properties in a saturated bentonite sand mixture under flexible boundary conditions
Soils and Foundations, 2018Co-Authors: Shuaibing Song, Hongyang Ni, Hai Pu, Frédéric SkoczylasAbstract:Abstract Gas Migration/breakthrough in saturated bentonite is an important issue for the evolution of the sealing ability of the engineered barrier in deep geological repositories. The main contribution of our study is to provide insights into the water and Gas transport properties in a compacted bentonite/sand mixture, which was wrapped by a flexible Viton™ membrane directly before being put into a triaxial cell. The experimental results indicate that the water permeability is very low and the magnitude is in the order of 10−20 m2. Gas breakthrough tests show that no continuous Gas flow was detected during the entire Gas breakthrough test (until the Gas pressure of 10 MPa), which indicates that the compacted bentonite/sand mixture has a good sealing ability after full saturation. Another important finding is that the Gas Migration properties are closely related to the stress state around the sample, the internal pore fluid pressure, and the creep effects caused by the two factors.
-
Gas Migration through water saturated bentonite sand mixtures cox argillite and their interfaces
Canadian Geotechnical Journal, 2016Co-Authors: Yang Song, Frédéric SkoczylasAbstract:France’s deep-seated nuclear waste repository consists of a natural barrier located at a depth of 500 m in a Callovo-Oxfordian clayey formation. This repository has artificial barriers that include plugs of swelling clay (MX80 bentonite – sand mixtures) for sealing purposes. This paper focuses on the Gas Migration properties of water-saturated bentonite–sand mixtures and their interfaces with COx argillite. The main contribution of our study is the identification of a preferential Gas Migration pathway by measuring the downstream Gas breakthrough pressures and Gas flow rates. The water permeabilities of the bentonite–sand mixtures and their interfaces with COx argillite or COx argillite itself are the same order of magnitude (10−20–10−21 m2). Thus, water tightness can be obtained for these materials when they become completely saturated. The results obtained from the Gas breakthrough tests suggest that both the COx argillite and its interface with the bentonite–sand mixture can act as preferential pathway...
-
Gas Migration into Low Permeability Callovo-Oxfordian Argillite
2nd EAGE International Conference on Fault and Top Seals - From Pore to Basin Scale 2009, 2009Co-Authors: J. Talandier, Frédéric Skoczylas, Bernhard M. Krooss, M. PratAbstract:Gas Migration into argillaceous formations is an important issue to evaluate the perturbation induced by Gas in an underground radioactive waste repository. The mechanisms controlling Gas entry and flow into clay media are not fully understood yet and have to be investigated. In that context, Andra and its partners developed an experimental program to characterize the Gas behavior of the Callovo-Oxfordian argillite which is the host rock for the French radioactive waste repository. Gas entry pressure and some key parameters such as Gas permeability have been measured. We present first the main experimental results obtained on argillite. Then, the analysis of the results leads to discussions about the two-phase flow model used to predict Gas Migration at the repository scale.
Shuaibing Song - One of the best experts on this subject based on the ideXlab platform.
-
research on Gas Migration properties in a saturated bentonite sand mixture under flexible boundary conditions
Soils and Foundations, 2018Co-Authors: Shuaibing Song, Hongyang Ni, Hai Pu, Frédéric SkoczylasAbstract:Abstract Gas Migration/breakthrough in saturated bentonite is an important issue for the evolution of the sealing ability of the engineered barrier in deep geological repositories. The main contribution of our study is to provide insights into the water and Gas transport properties in a compacted bentonite/sand mixture, which was wrapped by a flexible Viton™ membrane directly before being put into a triaxial cell. The experimental results indicate that the water permeability is very low and the magnitude is in the order of 10−20 m2. Gas breakthrough tests show that no continuous Gas flow was detected during the entire Gas breakthrough test (until the Gas pressure of 10 MPa), which indicates that the compacted bentonite/sand mixture has a good sealing ability after full saturation. Another important finding is that the Gas Migration properties are closely related to the stress state around the sample, the internal pore fluid pressure, and the creep effects caused by the two factors.
Hai Pu - One of the best experts on this subject based on the ideXlab platform.
-
research on Gas Migration properties in a saturated bentonite sand mixture under flexible boundary conditions
Soils and Foundations, 2018Co-Authors: Shuaibing Song, Hongyang Ni, Hai Pu, Frédéric SkoczylasAbstract:Abstract Gas Migration/breakthrough in saturated bentonite is an important issue for the evolution of the sealing ability of the engineered barrier in deep geological repositories. The main contribution of our study is to provide insights into the water and Gas transport properties in a compacted bentonite/sand mixture, which was wrapped by a flexible Viton™ membrane directly before being put into a triaxial cell. The experimental results indicate that the water permeability is very low and the magnitude is in the order of 10−20 m2. Gas breakthrough tests show that no continuous Gas flow was detected during the entire Gas breakthrough test (until the Gas pressure of 10 MPa), which indicates that the compacted bentonite/sand mixture has a good sealing ability after full saturation. Another important finding is that the Gas Migration properties are closely related to the stress state around the sample, the internal pore fluid pressure, and the creep effects caused by the two factors.
Hongyang Ni - One of the best experts on this subject based on the ideXlab platform.
-
research on Gas Migration properties in a saturated bentonite sand mixture under flexible boundary conditions
Soils and Foundations, 2018Co-Authors: Shuaibing Song, Hongyang Ni, Hai Pu, Frédéric SkoczylasAbstract:Abstract Gas Migration/breakthrough in saturated bentonite is an important issue for the evolution of the sealing ability of the engineered barrier in deep geological repositories. The main contribution of our study is to provide insights into the water and Gas transport properties in a compacted bentonite/sand mixture, which was wrapped by a flexible Viton™ membrane directly before being put into a triaxial cell. The experimental results indicate that the water permeability is very low and the magnitude is in the order of 10−20 m2. Gas breakthrough tests show that no continuous Gas flow was detected during the entire Gas breakthrough test (until the Gas pressure of 10 MPa), which indicates that the compacted bentonite/sand mixture has a good sealing ability after full saturation. Another important finding is that the Gas Migration properties are closely related to the stress state around the sample, the internal pore fluid pressure, and the creep effects caused by the two factors.
S A Henrys - One of the best experts on this subject based on the ideXlab platform.
-
Gas Migration into Gas hydrate‐bearing sediments on the southern Hikurangi margin of New Zealand
Journal of Geophysical Research, 2015Co-Authors: Gareth Crutchley, D R A Fraser, I A Pecher, A R Gorman, G Maslen, S A HenrysAbstract:We present multichannel seismic data from New Zealand's Hikurangi subduction margin that show widespread evidence for Gas Migration into the field of Gas hydrate stability. Gas Migration along stratigraphic layers into the hydrate system manifests itself as highly reflective segments of dipping strata that originate at the base of hydrate stability and extend some distance toward the seafloor. The highly reflective segments exhibit the same polarity as the seafloor reflection, indicating that localized Gas hydrate precipitation from Gas-charged fluids within relatively permeable layers has occurred. High-density velocity analysis shows that these layer-constrained Gas hydrate accumulations are underlain by thick (up to ~500 m) free Gas zones, which provide the source for focused Gas Migration into the hydrate layer. In addition to Gas being channeled along layers, we also interpret Gas Migration through a fault zone into the field of hydrate stability; in this case, a low-velocity layer within the hydrate stability zone extends laterally away from the fault, which might indicate that Gas-charged fluids have also migrated away from the fault along strata. At this site, where both dipping strata and faulting seem to influence fluid Migration, we observe anomalously high velocities at the base of hydrate stability that we interpret as concentrated Gas hydrates. Our results give insight into how shallow fluid flow responds to permeability contrasts between strata, fault zones, and perhaps also the Gas hydrate system itself. Ultimately, these relationships can lead to Gas Migration across the base of hydrate stability and the precipitation of concentrated hydrate deposits.
-
Gas Migration into Gas hydrate bearing sediments on the southern hikurangi margin of new zealand
Journal of Geophysical Research, 2015Co-Authors: Gareth Crutchley, D R A Fraser, I A Pecher, A R Gorman, G Maslen, S A HenrysAbstract:We present multichannel seismic data from New Zealand's Hikurangi subduction margin that show widespread evidence for Gas Migration into the field of Gas hydrate stability. Gas Migration along stratigraphic layers into the hydrate system manifests itself as highly reflective segments of dipping strata that originate at the base of hydrate stability and extend some distance toward the seafloor. The highly reflective segments exhibit the same polarity as the seafloor reflection, indicating that localized Gas hydrate precipitation from Gas-charged fluids within relatively permeable layers has occurred. High-density velocity analysis shows that these layer-constrained Gas hydrate accumulations are underlain by thick (up to ~500 m) free Gas zones, which provide the source for focused Gas Migration into the hydrate layer. In addition to Gas being channeled along layers, we also interpret Gas Migration through a fault zone into the field of hydrate stability; in this case, a low-velocity layer within the hydrate stability zone extends laterally away from the fault, which might indicate that Gas-charged fluids have also migrated away from the fault along strata. At this site, where both dipping strata and faulting seem to influence fluid Migration, we observe anomalously high velocities at the base of hydrate stability that we interpret as concentrated Gas hydrates. Our results give insight into how shallow fluid flow responds to permeability contrasts between strata, fault zones, and perhaps also the Gas hydrate system itself. Ultimately, these relationships can lead to Gas Migration across the base of hydrate stability and the precipitation of concentrated hydrate deposits.
