Portal de Periódicos da CAPES

Wettability Effects on Oil-Recovery Mechanisms in Fractured Reservoirs

2001; Volume: 4; Issue: 06 Linguagem: Inglês

10.2118/74335-pa

1930-0212

A. Graue, Thomas Bognø, Bernard A. Baldwin, Eugene A. Spinler,

Hydrocarbon exploration and reservoir analysis

Summary Iterative comparison between experimental work and numerical simulations has been used to predict oil-recovery mechanisms in fractured chalk as a function of wettability. Selective and reproducible alteration of wettability by aging in crude oil at an elevated temperature produced chalk blocks that were strongly water-wet and moderately water-wet, but with identical mineralogy and pore geometry. Large scale, nuclear-tracer, 2D-imaging experiments monitored the waterflooding of these blocks of chalk, first whole, then fractured. This data provided in-situ fluid saturations for validating numerical simulations and evaluating capillary pressure-and relative permeability-input data used in the simulations. Capillary pressure and relative permeabilities at each wettability condition were measured experimentally and used as input for the simulations. Optimization of either Pc-data or kr-curves gave indications of the validity of these input data. History matching both the production profile and the in-situ saturation distribution development gave higher confidence in the simulations than matching production profiles only.