Laboratory study on profile control visualization of fractured vuggy reservoirs

The reservoir space is complex, the remaining oil distribution is not clear, and the bottom water channeling along the dominant channel is the current production problem of the fractured vuggy reservoir. This paper designs the visual physical models of the fractured vuggy reservoir and the fractured net reservoir according to the similarity criteria, intuitively analyzes the generation mechanism of "attic oil", studies the model recovery, water cut change and remaining oil distribution of the bottom water drive under different speeds, and the EOR mechanism of gel profile control. The results show that the generation of "attic oil" is mainly caused by the difference between oil and water gravity. If the fracture communication location is at the high part of the karst cave, the bottom water drive can spread to more areas, and the "attic oil" is less; Properly reducing the bottom water drive speed can replace oil and water, and improve oil recovery to a certain extent; silicic acid gel blocks the bottom of fractures and holes and improves oil recovery and improves local oil-water profile, but bottom water is still easy to cross flow through other advantageous channels.