Gamma-camera imaging of oil displacement in thin slabs of porous media

Experiments are reported in which a gamma camera is used to observe fluid displacement in thin slabs of porous media. Technetium-99m (half-life of 6.5 hours) is used as tracer for water phase and gamma ray activity measured over a 64 x 64 picture field in which each pixel is 4 x 4 mm. A method for image enhancement is applied. The gamma camera gives a quantitative determination of local fluid saturations over the area of observation.