Restored-state core analysis for the Hutton reservoir

Journal Article · Tue Dec 01 04:00:00 EST 1987 · SPE (Society of Petroleum Engineers) Format. Eval.; (United States)

DOI:https://doi.org/10.2118/14298-PA· OSTI ID:5663384

Wendel, D J; Anderson, W G; Meyers, J D

Wettability is a major control parameter in multiphase flow analyses such as relative permeability. When such analyses are required, the native wettability of the reservoir must be maintained in the test plug. Unfortunately for laboratory analyses, cores are increasingly being taken with wettability-altering, oil-based, surfactant-containing muds. When a core's wettability has been altered by such drilling fluids, special procedures must be used to obtain proper analyses. First, the core plug must be cleaned of wettability-altering contaminants, then restored to reservoir wettability using uncontaminated native crude before accurate relative permeabilities can be obtained. These special cleaning and restoration procedures are described for cores from the Hutton field, located in the U.K. sector of the North Sea. Plugs taken from Hutton cores were contaminated with invert-oil-emulsion drilling mud, which made them strongly oil-wet. By use of special cleaning methods, the surfactants from the drilling mud were removed, and the Hutton reservoir was subsequently shown to be only slightly oil-wet by use of relative permeabilities on plugs that had been restored to native wettability. It was also found that some sections of the Hutton cores were neutral-wet to slightly oil-wet even when clean, possibly because of the presence of coal.

• Research Organization: Conoco Inc.
• OSTI ID: 5663384
• Journal Information: SPE (Society of Petroleum Engineers) Format. Eval.; (United States), Journal Name: SPE (Society of Petroleum Engineers) Format. Eval.; (United States) Vol. 2:4; ISSN SFEVE
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
ACCURACY
ATLANTIC OCEAN
COLLOIDS
DISPERSIONS
DRILL CORES
DRILLING FLUIDS
EMULSIONS
EUROPE
FLUID FLOW
FLUIDS
GEOLOGIC DEPOSITS
GEOPHYSICS
IMPURITIES
MINERAL RESOURCES
MULTIPHASE FLOW
NORTH SEA
OIL SATURATION
PERMEABILITY
PETROLEUM DEPOSITS
PURIFICATION
RESERVOIR ROCK
RESOURCES
SATURATION
SEAS
SURFACE WATERS
SURFACTANTS
TESTING
UNITED KINGDOM
WESTERN EUROPE
WETTABILITY