Oil & Natural Gas Projects
Exploration and Production Technologies
Multiphase Fracture-Matrix Interactions Under Stress Changes
This project was selected in response to DOE Oil Exploration and Production
solicitation DE-PS26-04NT15450-3B, with a focus on Enhanced Oil Recovery. One
goal of the solicitation was to promote understanding of fractures and methods
for increasing oil recovery.
The main objective of this project is to quantify the changes in fracture porosity
and structure and multi-phase transport properties, including fracture-matrix
interactions, as a function of confining stress. Extensional and shear fractures
Pennsylvania State University
University Park, PA
The project achieved the ability to map in three dimensions the distribution
of oil and water in a fracture and relate that distribution to effective permeability
at various fractional flows-including hysteresis effects-and to fracture-matrix
The results provide new understanding of two-phase flow in fractures, including
fracture-matrix interactions, and should improve modeling of fluid transport
in fractured formations.
The main driver for the project is the great need to accurately model and optimize
transport in fractured systems, in order to improve industry's limited understanding
of the detailed physics of these transport phenomena.
Among the project's achievements:
- Fracture topoplogy was obtained using x-ray computed tomography (CT) to include
fracture surfaces, fracture volume, and structural relation to the matrix.
- Oil and water occupancy in the fracture was measured by CT and related to
effective permeabilities of the two phases.
- Counter-current imbibition between the fracture and the matrix was documented
and quantified and shown to be significant and rapid.
- Effects of changing confining stress on fracture properties have been quantified,
including the changes in occupancy and transport of oil and water. Significant
differences in oil-water occupancies in shear fractures parallel and perpendicular
to bedding were observed.
Current Status (August 2005)
The project is proceeding under a 1 year, no-cost extension and will be completed
by Sept. 20, 2005.
Seven semi-annual reports to DOE. Two MSc and two PhD theses.
Karpyn, Z., Alajmi, A., Parada, C., Grader, A., Halleck, P., and Karacan,
O., Mapping Fracture Apertures Using Micro-Computed Tomography, The Society
of Core Analysis 2003 International Symposium, Pau-France. SCA2003-50, p.
Nazridoust, K., Ahmadi, G., Karpyn, Z., Grader, A., Halleck, P., Mazaheri,
A., and Smith, D., Single-Phase and Multi-Phase Fluid Flow through an Artificially
Induced, CT-Scanned Fracture, 15th International Conference on Computational
Methods in Water Resources, June 13-17, 2004, Chapel Hill, NC.
Karpyn, Z., Alajmi, A., Radaelli, F., Halleck, P.M., and Grader, A.S., A Correlation
between Fracture Apertures and Properties of the Surrounding Layered Sandstone
Matrix, 32nd International Geological Congress, Aug. 20-28, 2004, Florence,
Mohammed, N., Al Enezi, S., Halleck, P. M., Elsworth, D., and Grader, A. S.,
Effects of Bedding Plane Orientations on Two-Phase Flow in Shear Fractures.
Eos Trans. AGU, 85(47), Fall Meeting Supplement, Abstract H11B-0300, 2004.
Karpyn, Z., Halleck, P. M., Grader, A. S., and Elsworth, D., Dynamic Micro-CT
Study of Fracture-Matrix Flow during Capillary Imbibition in Layered Berea
Sandstone. Eos Trans. AGU, 85(47), Fall Meeting Supplement, Abstract H11B-0297,
Karpyn, Z. T., Grader, A. S., and Halleck, P.M., Characterization of two-phase
fluid residence inside a fracture with variable aperture, In Preparation for
Karpyn, Z. T., Halleck, P.M., and Grader, A.S., Fracture-matrix transport
dominated by capillary-driven flow in layered sandstone, Water Resources Research,
submitted for review (2005WR004371), 2005.
Water imbibing from fracture, top left. Disconnected oil globs within the
fracture at residual oil saturation, top right. Three-dimensional renditions
of a shear fracture in a layered sample. Fracture asperities (red) at 500
psig (left) and 2,500 psig (right).
Project Start: Sept. 21, 2001
Project End: Sept. 20, 2005
Anticipated DOE Contribution: $439,887
Performer Contribution: $110,154 (25% of total)
NETL - Virginia Weyland (firstname.lastname@example.org or 918-699-2041)
Penn State University - Abraham S. Grader (email@example.com or 814-865-5813)