Groundwater flow models numerical

The actual calculations were performed using balance, an earlier inverse mass balance modeling code that is now superseded by netpath and phreeqc. Chapelle and Lovley (1990) then calculated the time interval in these segments from flow velocities calculated by a numerical groundwater flow model and the length of the flow path. The total CO2 production rate from oxidation of organic matter is... 

Narasimhan, T.N. (1975). A unified numerical model for saturated-unsaturated groundwater flow. Thesis. University of California, Berkeley, Berkeley, CA. 

Groundwater Flow. 1. Analytical and Numerical Solutions to the Mathematical Model, Water Resources Res. (1966) 2 (4), 641-656. 

Numerical groundwater flow, transport, and geochemical models are important tools besides classical deterministic and analytical approaches. Solving complex linear or non-linear systems of equations, commonly with hundreds of unknown parameters, is a routine task for a PC. 

To analyze the transport and retention of chemical contaminants in groundwater flowing through soils, experimental and theoretical studies generated several reliable models. Diverse numerical methods have been applied to solve the governing equations efficiently. Some computer models include the simulation of physical and chemical processes. 

Garven G. and Freeze R. A. (1984a) Theoretical analysis of the role of groundwater flow in the genesis of stratabound ore deposits 1. Mathematical and numerical model. Am. J. Sci. 284, 1085-1124. 

Huguet J. M. (2001) Testing and validation of numerical models of groundwater flow, solute transport and chemical reactions in fractured granites a quantitative study of the hydrogeological and hydrochemical impact produced. ENRESA Tech. Publ. 06/2001, 253pp. 

At the aquifer scale, the most important contribution of age tracers is probably reduction in the nonuniqueness of numerical models. Lack of uniqueness stems, among other things, from inadequate knowledge of the distribution of hydraulic properties within groundwater systems and from poor constraints on boundary conditions (Konikow and Bredehoeft, 1992 Maloszewski and Zuber, 1993). Commonly, groundwater flow... 

Freeze R. A. and Witherspoon P. A. (1966) Theoretical analysis of regional groundwater flow 1. Analytical and numerical solutions to the mathematical model. Water Resour. Res. 2, 623-634. 

Phillips F. M., Tansey M. D., Peelers L. A., Cheng S., and Long A. (1989) An isotopic investigation of groundwater in the central San Juan Basin, New Mexico carbon-14 dating as a basis for numerical flow modeling. Water Resour. Res. 25, 2259-2273. 

Permeabilities in sedimentary basins are known to vary with the scale of observation (e.g. Bredehoeft et al., 1983,1992 Chapman et al, 1991 Neuzil, 1986). Different techniques are being developed to estimate reservoir- and basin-scale permeabilities, e.g. computer-aided techniques based on relations between characteristics of depositional systems and permeability distribution (Weber, 1982,1987 Stam, 1989 Stam et al., 1989 Mijnssen, 1991), and techniques based on numerical simulations of basin-scale groundwater flow in combination with known groundwater pressure distributions (e.g. Bredehoeft et al., 1983, 1992 Burrus et al., 1991), techniques that use numerical models of coupled groundwater flow/heat flow and known thermal characteristics to estimate basin-scale permeabilities (Chapman et al., 1991). 

Although water resource issues seemingly concern the movement of water only (flow problems versus transport problems), the chemical constituents in groundwater and their movement may actually help to delineate the flow system that hydraulic data alone fail to reveal. An important limitation for numerical modeling of groundwater flow in the saturated zone is the limited availability of hydraulic parameters and the... 

It was found that the subsidence of the ground surface is a result of coupled effects between groundwater flow and rock/soil deformation, with the seepage and consolidation affected by changes in rock/soil porosity and permeability. Numerical modelling using coupled flow-deformation models become necessary. 

A regional numerical model produced by Vobomy et al. (1991) has provided an estimate of the main flows within a vicinity of several kilometres around the GTS, while a second model has allowed deriving more details of the site area. These models have been used as references to infer boundary conditions for the more heavily-localized model performed. Two shear zones (K and S) located within the vicinity of the FEBEX tunnel constrain groundwater flow due to their high transmissivity and therefore constitute FEBEX environment boundaries in subsequent model, they have been considered as imposed head limits (see Figure 3). 

Over the past two decades AECL has developed a three-dimensional code, MOTIF (Model Of Transport In Fractured/porous media), for detailed modelling of groundwater flow, heat transport, mechanical equilibrium and solute transport in a fractured rock mass. The initial development was completed in 1985 (Guvanasen 1985). Since then the code has undergone extensive updating, verification - comparison with known analytical or numerical solutions - and validation - comparison with experiments - (Chan et al. 2(XX)). In the latter document sixteen test cases were repotted to verify the code for groundwater flow, heat transfer and solute transport in fractured or porous rock. In this paper, additional verification and validation studies with an emphasis on thermo-hydromechanical (T-H-M) processes are presented. 

As it has been shown by the investigations, there are several sites within overall field area (340 -400 km") typified by the presence of concentrated heat sources developed in the foundation rocks which are the basement for the volcanogenic-sedimentary strata forming the field (Kiryukhin, 1996). The Middle site of the Paratoon field (2.4 -3.5 km) associated with the northern part of Paratoon hydrothermal system is one of the most perspective in the aspect of thermal waters numerical modeling of groundwater flow and heat exchange processes has been carried out with the orientation to its hydrogeologic conditions. 

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