HR: 1340h
AN: H13C-1390    [Abstracts]
TI: Characterization of Fracture Capillary Pressure from Geo-statistical Analysis of Rough Fracture Structures
AU: * Petchsingto, T
EM: txp192@psu.edu
AF: The Pennsylvania State Univerisity, 110 Hosler Building Department of Energy and Mineral Engineering, University Park, PA 16802, United States
AU: Karpyn, Z
EM: ztk101@psu.edu
AF: The Pennsylvania State Univerisity, 110 Hosler Building Department of Energy and Mineral Engineering, University Park, PA 16802, United States
AB: The importance of the effect of fracture morphology on the flows of fluids through fractures has been extensively recognized. Nevertheless, understanding of the correlation between geostatistical parameters of fractures and macroscopic transport properties remains limited. The aim of this contribution is to examine the effect of geostatistical characteristics of fractures on the capillary pressure curves. The study model implements a modified invasion percolation (MIP) approach for modeling primary drainage which had been conducted in the previous experiment. MIP is the invasion percolation including normal and in-plane curvature terms of the fluid interface for calculating the local capillary pressure which indicates the least resistant path for invading fluid to flow through. The lattice model for the simulation is constructed from geometric structure of the fracture which was measured using a high resolution Computed Tomography (CT). The simulation results concur with 70% match of CT images of fluid distribution maps. A satisfactory agreement with the experimental results enables us to further study the characterization of capillary pressure for a wide range of the fracture structures having different geostatistical characteristics. The generation of fracture replicas is based on a matrix decomposition technique. Mean, spatial correlation length and variance of the aperture distribution are the geostatistical parameters used in the generator to characterize the replicas. The results show that the connectivity of the fractures strongly influences on the shape of the capillary pressure curve, and the connectivity can be quantified from the calculation of aperture variance and spatial correlation length.
DE: 1805 Computational hydrology
SC: Hydrology [H]
MN: 2007 Fall Meeting