HR: 1340h
AN: H53E-1461    [Abstracts]
TI: The Effects of a Shear Fracture on Multi-phase Transport in a Layered Sandstone
AU: * Al Enezi, S
EM: sma219@psu.edu
AF: The Pennsylvania State University, 204 Academic Activities, University Park, PA 16802, United States
AU: Halleck, P M
EM: pmh2@psu.edu
AF: The Pennsylvania State University, 204 Academic Activities, University Park, PA 16802, United States
AU: Grader, A S
EM: grader@ems.psu.edu
AF: The Pennsylvania State University, 204 Academic Activities, University Park, PA 16802, United States
AB: This research studies multi-phase transport in a sandstone core in the presence of a shear fracture. The cylindrical sample was cored parallel to bedding and placed in a Hoek cell that provided 10-Mpa confining stress on the sample. The sample was fractured in shear using offset shims to produce a fracture parallel to the axial bedding planes. After the initial breakdown, the fracture was displaced by about one percent of its initial length. The absolute permeability was measured by the Klinkenberg gas permeability method and by vacuum-saturated water flow. The absolute permeability of the fractured rock increased three fold when measured at a hydrostatic stress equal to the confining stress used for fracturing. A seqence of oil floods, water floods and fractional flow experiments were used to obtain relative permeability data in the fractured rock. The effective permeability to oil at residual water was high and the effective permeability to water at residual oil was very low. This indicates that once the large fracture volumes are filled with oil, they contribute only to oil flow and not to water flow. The distribution of oil and water in the large fractured region was established using Micro-Computed Tomography. This distribution confirms that most of the oil cannot be displaced out of the fracture and forces the water to flow in the matrix, thus yielding very low effective water permeabilities. Water-oil steady-state fractional flow trajectories were stable and confirmed a limited mobile saturation range in the fracture.
DE: 1859 Rocks: physical properties
SC: Hydrology [H]
MN: 2007 Fall Meeting