HR: 0830h
AN: H11G-0917    [PDF]
TI: Numerical modeling of laboratory permeability upscaling experiments
AU: Jaynes, J
EM: jjayne@nmt.edu
AF: Earth and Environmental Sciences Department, New Mexico Institute of Mining and Technology, Socorro, NM 87801 United States
AU: * Lowry, T S
EM: tslowry@sandia.gov
AF: Sandia National Laboratory, P.O. Box 5800 MS 0735, Albuquerque, NM 87185-0735 United States
AU: Tidwell, V C
EM: vctidwe@sandia.gov
AF: Sandia National Laboratory, P.O. Box 5800 MS 0735, Albuquerque, NM 87185-0735 United States
AU: Williams, J L
EM: jwilson@nmt.edu
AF: Earth and Environmental Sciences Department, New Mexico Institute of Mining and Technology, Socorro, NM 87801 United States
AB: Aquifer/reservoir characterization and the subsequent integration of acquired spatial information into predictive flow and transport models face two basic limitations. First, the quantity of porous media observed and/or sampled is generally a minute fraction of the site under investigation. This gives rise to the need for models to predict material characteristics at unsampled locations. Secondly, technological constraints limit the measurement of material properties to sample supports (volume of porous media sampled) that are much smaller than those that can be accommodated in current predictive models. The linkage of these two limitations becomes the global problem of upscaling measurement data to the domain of interest. As part of the evolution of addressing this problem, laboratory experiments have been performed to physically explore permeability upscaling. The experiments make use of a gas permeameter that has been specially adapted for acquiring permeability measurements over a range of discrete sample supports subject to consistent flow and boundary conditions. Thousands of permeability measurements were made at four discrete sample supports for various rock samples. At each scale, two-dimensional maps of permeability across the surface of each rock sample were constructed. The experimental results exhibited strong, consistent trends in the mean, variance, and semivariogram of the permeability as a function of sample support. These distinct trends provide physical evidence of upscaling and insight into the factors that influence this behavior. To extend the value of the experimental results, this work uses a numerical model to reproduce the experimental data. The use of a numerical model allows for the creation of functional relationships between instrumentation, sample size, and other variables to measured permeability, while eliminating experimental and measurement error. These numerical experiments explore the relationship between tip-seal size, sample support, and rock sample size. In addition, Monte Carlo analysis on multiple heterogeneous fields at various sample supports attempts to recreate the experimental trends in mean, variance, and semivariogram measured on the different rock samples. The importance of this effort is two fold: first is it provides a means of interpreting the experimental results and secondly, it provides a foundation and means for future work in the investigation of the relationship between heterogeneity, scale and instrumentation for a broader suite of geologic materials and measurement tools.
DE: 1829 Groundwater hydrology
DE: 1899 General or miscellaneous
DE: 5114 Permeability and porosity
DE: 5139 Transport properties
DE: 5194 Instruments and techniques
SC: Hydrology [H]
MN: 2003 Fall Meeting