Interrelationships and variations of the resistivity, porosity, and permeability as functions of pressure in a geopressured reservoir. Master's thesis

Technical Report · Sat Aug 01 04:00:00 EDT 1981

OSTI ID:5294327

Ashman, T R

Fluid production from both normally and abnormally pressured reservoirs has long been recognized as a function of the formation fluid properties and the reservoir rock parameters. Fluid production itself, however, changes the stress state of the reservoir resulting in rock deformation which affects total fluid and, therefore, energy recovery. This study was undertaken as part of a project to determine and predict the effects of fluid production on the Pleasant Bayou geopressured, geothermal reservoir in Brazoria County, Texas. Data was collected from triaxial loading tests conducted on sandstone samples cored from the potential producing horizons of the reservoir. All tests were conducted at overburden and pore pressures which simulated insitu conditions. Empirical relations were developed which reflected changes in the resistivity, porosity, and permeability as functions of the effective stress. Relationships among the parameters were found to be of practical use in predicting formation changes as the reservoir stress state changed due to fluid withdrawal. Results showed that the resistivity, porosity, and permeability were dependent on the effective stresses in the reservoir. The cementation factor in Archie's equation was also found to be a pressure function.

• Research Organization: Air Force Inst. of Tech., Wright-Patterson AFB, OH (USA)
• OSTI ID: 5294327
• Report Number(s): AD-A-108116/5; AFIT-CI-81-61T
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150904* -- Geothermal Engineering-- Geothermal Reservoir & Well Performance
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ENERGY SYSTEMS
FLUID WITHDRAWAL
FLUIDS
FUELS
GEOPRESSURED SYSTEMS
GEOTHERMAL FLUIDS
HYDROSTATICS
LEVELS
MECHANICS
PERMEABILITY
PHYSICAL PROPERTIES
POROSITY
RECOVERY
RESERVOIR PRESSURE
ROCK MECHANICS
STRESSES
UNDERGROUND