A 3D Geological Modeling for Complex Gas-Water Fluid Distribution in Tight Sandstone Reservoirs

The fluid distribution in tight sandstone reservoirs is seriously complicated by diagenesis and tectonic adjustment during or after petroleum accumulation. Gas-bearing (or gas saturation) prediction based on height function or reservoir porosity fitting calculation is no longer applicable. In this paper, a new technical process of gas-water layer modeling in tight sandstone reservoirs is introduced. According to the main controlling factors of gas and water distribution, different gas-bearing reservoir model is constructed to show the overall gas-bearing spatial distribution. Under multi-level facies control, the gas-water layer model is established by using geostatistical simulation, and the gas-bearing reservoir model is used to define the gas-water proportion and longitudinal differentiation, so as to realize the goal of quantitative characterization from the qualitative recognition. The research results provide a more accurate quantitative geological model for the complex fluid distribution of tight sandstone reservoirs.