The use of capillary pressure data for rapid evaluation of formation damage or stimulation

Conference · Wed Feb 01 04:00:00 EST 1984 · Soc. Pet. Eng. AIME, Pap.; (United States)

OSTI ID:6868584

Amaefule, J O; Masuo, S T

This paper presents the results of a systematic laboratory assessment of formation damage or stimulation through the use of the ultracentrifuge generated gas-water or oil-water drainage capillary pressure data. The technique utilizes the relative changes in the pore entry pressure, the shape of the capillary pressure function, and the residual wetting phase saturations as measures of damage or stimulation in cores exposed to various treatment fluids. Capillary pressure data obtained from Berea sandstone and field core samples with prior exposure to acids, completion and drilling fluids, and clay stabilizers were found to exhibit the following characteristics: capillary pressures and residual wetting phase saturations, S /SUB wr/ , increased with damage; damaged samples showed higher pore entry pressures, P /SUB d/ ; clay stabilized samples had lower capillary pressures and lower residual saturations; effective acid stimulation with adequate overflush resulted in lower entry pressures, lower residual saturations, and in wider pore size distributions, stimulation without overflush resulted in core damage, relative changes in permeability following damage or stimulation can be predicted from an index. The results of this study could be particularly useful to those involved in laboratory screening of several drilling, completion and stimulation fluids for field application. The capillary pressure technique can also be used to determine the optimal acid or clay stabilizer concentration which is compatible with a particular reservoir lithology. Most importantly, the technique compliments the more-time-consuming core flow test procedure.

• Research Organization: Occidental Research Co.
• OSTI ID: 6868584
• Report Number(s): CONF-840259-
• Conference Information: Journal Name: Soc. Pet. Eng. AIME, Pap.; (United States) Journal Volume: SPE-12475
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030900 -- Natural Gas-- Artificial Stimulation
Plowshare-- (-1989)
ACIDIZATION
DRILL CORES
DRILLING FLUIDS
ENGINEERING
FLUID MECHANICS
FLUIDS
FORECASTING
FORMATION DAMAGE
HYDRODYNAMICS
LITHOLOGY
MECHANICS
NATURAL GAS WELLS
OIL WELLS
PERMEABILITY
PORE PRESSURE
RESERVOIR ENGINEERING
RESERVOIR ROCK
ROCK-FLUID INTERACTIONS
ROCKS
SANDSTONES
SEDIMENTARY ROCKS
STIMULATION
WELL COMPLETION
WELL STIMULATION
WELLS