Assessment of the role of facies heterogeneity at the fine scale by numerical transport experiments and connectivity indicators

Vassena, Chiara; Cattaneo, Laura; Giudici, M.

doi:10.1007/s10040-009-0523-2

Cited by 25 publications

(30 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…What is the impact of connectivity on 3D continuous fields for various standard models? Very few studies considered 3D configurations [152,117]. From partial studies and theoretical considerations, we expect the connectivity behavior to be quantitatively and perhaps qualitatively different in 3D than in 2D.…”

Section: Research Needsmentioning

confidence: 99%

Connectivity metrics for subsurface flow and transport

Renard

Allard

2013

Advances in Water Resources

339

258

View full text Add to dashboard Cite

a b s t r a c tUnderstanding the role of connectivity for the characterization of heterogeneous porous aquifers or reservoirs is a very active and new field of research. In that framework, connectivity metrics are becoming important tools to describe a reservoir. In this paper, we provide a review of the various metrics that were proposed so far, and we classify them in four main groups. We define first the static connectivity metrics which depend only on the connectivity structure of the parameter fields (hydraulic conductivity or geological facies). By contrast, dynamic connectivity metrics are related to physical processes such as flow or transport. The dynamic metrics depend on the problem configuration and on the specific physics that is considered. Most dynamic connectivity metrics are directly expressed as a function of an upscaled physical parameter describing the overall behavior of the media. Another important distinction is that connectivity metrics can either be global or localized. The global metrics are not related to a specific location while the localized metrics relate to one or several specific points in the field. Using these metrics to characterize a given aquifer requires the possibility to measure dynamic connectivity metrics in the field, to relate them with static connectivity metrics, and to constrain models with those information. Some tools are already available for these different steps and reviewed here, but they are not yet routinely integrated in practical applications. This is why new steps should be added in hydrogeological studies to infer the connectivity structure and to better constrain the models. These steps must include specific field methodologies, interpretation techniques, and modeling tools to provide more realistic and more reliable forecasts in a broad range of applications.

show abstract

Section: Research Needsmentioning

confidence: 99%

Connectivity metrics for subsurface flow and transport

Renard

Allard

2013

Advances in Water Resources

339

258

View full text Add to dashboard Cite

show abstract

“…The results of Vassena et al (2010) show that in alluvial sediments typical effects of preferential flow paths might appear in the presence of connected permeable structures, even with rather limited conductivity contrasts, i.e. even if the distinction between two regions where water is mobile or immobile is not appropriate.…”

mentioning

confidence: 95%

“…Other applications of DDMs focused on transport of solutes in partially saturated media or structured soils (Coats and Smith 1964;van Genuchten and Wierenga 1976;Skopp et al 1981;Gerke and van Genuchten 1993;Ma and Selim 1995;Gerke and van Genuchten 1996;Larsson and Jarvis 1999;Feehley et al 2000;Harvey and Gorelick 2000;Schwartz et al 2000;Flach et al 2004). Most of these models are of mobile-immobile type, also called stagnant-region models, as they subdivide the domain in a mobile region, where transport is dominated by convection, and an immobile region, where transport mainly occurs by molecular diffusion.…”

mentioning

confidence: 97%

“…In particular the hydrofacies heterogeneity at fine scale might affect the fate of contaminants at the scale of the depositional elements (Heinz and Aigner 2003). Vassena et al (2010) studied convective solute transport in three model blocks of alluvial sediments (volumes of a few cubic meters) at the scale of depositional elements to assess the effect of the heterogeneity at the hydrofacies scales. Some numerical transport experiments highlighted the existence of preferential flow paths, which were recognised and analysed in similar geological environments by, among others, Poeter and Townsend (1994), Ptak and Teutsch (1994), Anderson et al (1999), LaBolle et al (2006), Guan et al (2008) and Llopis-Albert and Capilla (2009).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Single and Dual-Domain Models to Evaluate the Effects of Preferential Flow Paths in Alluvial Sediments

2010

Self Cite

View full text Add to dashboard Cite

Typical features of preferential flow paths were evidenced by numerical tests of convective transport of conservative solutes performed in three blocks of alluvial sediments at the scale of depositional elements. The numerical experiments are analysed with standard single-domain models (SDMs) and with dual-domain models (DDMs): the model parameters are identified by minimisation of the misfit between the "experimental" and the modelled cumulative breakthrough curves (BTCs) and between the "experimental" and the modelled temporal moments of the BTCs. The results for the SDMs show different behaviours for the three model blocks and for the different flow directions, in good agreement with their hydrostratigraphic characteristics. The results for the DDMs sometimes correspond to cases for which one of the two domains is dominant and its values of diffusivity and average velocity are close to those obtained for the SDM; in some cases the DDM performs much better than the SDM and correctly represents the effects of preferential flow paths. Finally the relevance of the DDM is analysed in the framework of multi-objective optimisation: a proper choice of the objective-functions yields Pareto sets whose geometries are different for single-and dual-domain media.

show abstract

“…Within this background, the first goal of this paper is to propose a code, YAGMod (yet another groundwater flow model), developed in Fortran90, for the simulation of constant-density, groundwater flow under stationary conditions, which is the extension of the codes developed by our research team over the years [7][8][9][10][11][12][13][14][15][16][17]. YAGMod is based on a conservative finite difference scheme for stationary conditions and is oriented to the simulation of flow in saturated media.…”

Section: Introductionmentioning

confidence: 99%

Modeling Groundwater Flow in Heterogeneous Porous Media with YAGMod

et al. 2015

Self Cite

View full text Add to dashboard Cite

Abstract:Modeling flow and transport in porous media requires the management of complexities related both to physical processes and to subsurface heterogeneity. A thorough approach needs a great number of spatially-distributed phenomenological parameters, which are seldom measured in the field. For instance, modeling a phreatic aquifer under high water extraction rates is very challenging, because it requires the simulation of variably-saturated flow. 3D steady groundwater flow is modeled with YAGMod (yet another groundwater flow model), a model based on a finite-difference conservative scheme and implemented in a computer code developed in Fortran90.YAGMod simulates also the presence of partially-saturated or dry cells. The proposed algorithm and other alternative methods developed to manage dry cells in the case of depleted aquifers are analyzed and compared to a simple test. Different approaches yield different solutions, among which, it is not possible to select the best one on the basis of physical arguments. A possible advantage of YAGMod is that no additional non-physical parameter is needed to overcome the numerical difficulties arising to handle drained cells. YAGMod also includes a module that allows one to identify the conductivity field for a phreatic aquifer by solving an inverse problem with the comparison model method.

show abstract

Assessment of the role of facies heterogeneity at the fine scale by numerical transport experiments and connectivity indicators

Cited by 25 publications

References 22 publications

Connectivity metrics for subsurface flow and transport

Connectivity metrics for subsurface flow and transport

Single and Dual-Domain Models to Evaluate the Effects of Preferential Flow Paths in Alluvial Sediments

Modeling Groundwater Flow in Heterogeneous Porous Media with YAGMod

Contact Info

Product

Resources

About