Exploration and practice of gas driving in well groups with high water content in carbonate fractured-vuggy reservoirs

The carbonate fractured-vuggy reservoirs in the Tahe Oilfield are featured by high burial depth, super heterogeneity, various reservoir spaces and so on, with little previous experience resources to draw on and also rather restricted in effective measures available to combat high water cut issues for major well units. In order to keep oil production at a quite high and stable level, we need to do a feasibility study relating to injecting gas between well groups to enhance oil recovery. In this article, relevant theoretical models and mechanism for gas driving in well groups are deduced and the optimizing principles are also introduced through physical simulation experiments, by deeply studying gas injection development situations in China and abroad. Finally, by analyzing some practical cases, it is well-confirmed that gas driving in well groups shows a better performance for large carbonate fractured-vuggy reservoirs and provides new ideas and methods to enhance oil recovery and control the natural declination of such kind of reservoirs.