HR: 1340h
AN: H43F-0422    [Abstracts]
TI: Stochastic Upscaling of Transport and Retention in Two-Dimensional Discrete Fracture Networks.
AU: * Frampton, A
EM: frampton@kth.se
AF: Royal Institute of Technology, Brinellv 32 S-10044 Stockholm, Stockholm, S-10044 Sweden
AU: Painter, S
EM: spainter@swri.edu
AF: Southwest Research Institute, 6220 Culebra Road P.O. Drawer 28510 San Antonio, Texas 78228-0510, San Antonio, TX 78228-0510 United States
AB: Many natural phenomena are modelled as random processes despite being generally accepted as a complicated sequence of deterministic events. Tracer transport in discrete fracture networks is such a phenomena. Understanding the time evolution of a collection of tracer particles in groundwater flow is critical for the assessment of many environmental applications, such as subsurface containment of nuclear waste products. However, there is a difficulty in simulating flow in fractured rock at the geosphere scale due to the vast amount of fractures occuring at a multitude of scales. Efficient methods of upscaling are therefore necessary to predict tracer evolution through the geosphere barrier. We discuss the recently developed Markov-directed random walk (MDRW) method of upscaling tracer transport and retention in discrete fracture networks, and present results from stochastic two-dimensional flow simulations, along with MDRW calculations. We explore the asymptotic behaviour of the integrated random variables ($\tau$, $\beta$) which control advection and retention, and we consider how results of various scenarios affect the assumed relationship between $\tau$ and $\beta$, together with their implications to upscale modelling.
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting