Construction of Injection and Production Well Pattern for Fault-controlled Fractured-vuggy Carbonate Vertical Plate-shaped Reservoirs
The fracture-vuggy structure and connection relationship of fault-controlled fracture-vuggy carbonate reservoirs are complex,and traditional well pattern deployment is prone to produce low-productivity wells.A three-dimensional injection and production well pattern needs to be constructed to increase productivity.The influence of different factors on the sweep coefficient of the three-dimensional injection and production well pattern in the Manshen 3 and Manshen 4 well areas of the Tarim Fuman Oilfield was studied through reservoir numerical simulation,and a pilot test plan was designed to predict produc-tivity.The results show that the sweep coefficient is the largest when the gas injection wells and production wells are arranged in a single staggered manner in the Manshen 3 well area;the greater the depth of the production wells,the greater the sweep coefficient;the sweep coefficient is stable within the range of 500~1 000 m between injection and production wells,and de-creases significantly when the distance increases to 1 500 m.The sweep coefficient is the largest when gas injection wells,water injection wells and production wells are arranged in a single staggered manner in the Manshen 4 well area.In the pilot test,the plans of"N2 injection in the shallow part and production in the deep part"and"N2 injection in the top part,water injection in the bottom part,and production in the middle part"are adopted in the Manshen 3 and Manshen 4 well areas respectively.The recovery rates at the end of the stage reach 21.3%and 22.4%respectively,which is a significant improvement compared to the basic depletion development and water injection development plans.
Fuman Oilfieldfault-controlled fractured-vuggy reservoircarbonate rockthree-dimensional injection and pro-duction well patternwell pattern constructionsweep coefficient