HR: 1340h
AN: U43B-1126    [Abstracts]
TI: Flow Dimension and Anomalous Diffusion Coefficient as Potential Indicators of the Connectivity of a Fractured Aquifer
AU: * Cello, P A
EM: cello@uiuc.edu
AF: UIUC, Civil and Environmental Engineering (CEE) Department, 205 N. Mathews, Urbana, IL 61801, United States
AU: Walker, D D
EM: ddwalker@uiuc.edu
AF: Illinois State Water Survey, 2204 Griffith Dr., Champaign, IL 61820, United States
AU: Valocchi, A J
EM: valocchi@uiuc.edu
AF: UIUC, Civil and Environmental Engineering (CEE) Department, 205 N. Mathews, Urbana, IL 61801, United States
AU: Loftis, B
EM: bloftis@purdue.edu
AF: Purdue Universitu, Yong building west lafayette campus, Purdue, IN 47906, United States
AB: The General Radial Flow (GRF) interpretation of hydraulic tests presented by Barker (1988) has been increasingly applied in recent years due to its capability to address the complex geometry of fractured rock aquifers. This approach considers an additional parameter, namely the flow dimension n, to describe the flow geometry. While the published literature has addressed the analysis and characterization of connectivity in a fracture network system (Bour and Davy, 1997), few studies have related fracture connectivity to the behavior of pressure transients and the flow dimension. Studies relating the flow dimension to transport processes are scarcer still. The present work analyzes the connectivity of a fracture network system versus the behavior of the flow dimension and the anomalous diffusion coefficient. A discrete linear feature network with lengths distributed as a power-law is used to represent the connectivity of a fractured rock aquifer. An intensive Monte Carlo simulation of transient hydraulic tests then examines the effect of the connectivity on the behavior of the flow dimension and the diffusivity of the system at different spatial scales of the aquifer test. Preliminary results show that the behavior of the flow dimension and the diffusivity coefficient depend on the fracture length distribution, hence on the connectivity regime of the fracture network system. While the flow dimension stabilizes to a value less than the Euclidean dimension at late time of the aquifer test and for a particular connectivity regime, the diffusivity coefficient confirms the non-fickean behavior of the transport processes. Therefore, both the flow dimension and diffusivity coefficient could be used as potential indicators to identify connectivity regimes that better represent the observed behavior of flow and transport in fracture media.
DE: 9800 GENERAL OR MISCELLANEOUS
SC: Union [U]
MN: 2007 Fall Meeting