The probability of oil and water movement in tight sandstone: Evaluation methodology and mechanism analysis

Abstract

The mechanisms of oil and water movement in tight sandstone are complicated. Many factors, like pore structure, mineral component, liquid behavior and environment condition, have great influence on this oil and water movement process. The key influencing factors are still not fully revealed. In this work, we introduced fractal theory into pore space representation process, and then provided an effective model to evaluate the movement probability of oil and water in tight sandstone. This model has considered dominant influencing factors, like mineral wettability, pore roughness, and the behavior of pore space and liquid. On the basis of this model, the mobilization probability within different pores are discussed under different conditions. And finally, as a simple application, the mobilization probability is derived in different depth with complicated formation environment, which provides a new way to evaluate the oil and water mobilization mechanism in tight formation.