A Case Study on
Redevelopment of a Giant Highly Fractured Carbonate Field in
Camus, Denis1, Baham Samimi2, Mohammad Ghanizadeh3, Yves Coury1 (1) BEICIPFRANLAB, Rueil-Malmaison, France (2) NIOC/PEDEC-COPCEP, Tehran, Iran (3) Tehran Energy Consultants, Tehran, Iran
This field is located within the Zagros fold belt in the South West Iran and is producing in highly fractured carbonate Asmari and Bangestan reservoirs. It is a 70 km long anticline with about 50 billions barrels of initial oil in place and a small initial gas cap; initial oil column is 2000 m of 32 API crude with properties varying with depth. The field was discovered in 1937 and produced by natural depletion until 1977 when gas injection was initiated in the gas cap. A total of 320 wells were drilled on the structure. The study was based on an integrated reservoir characterization and on 3D modeling studies. A new Master Development Plan was proposed to maximize hydrocarbon recovery. This presentation will cover: (1)The reservoir characterization mainly based on rock-typing for both cored and non cored wells, on fracture characterization and modeling study and on the construction of a full field geostatistical fine grid model. (2) The reservoir simulations including phenomenological studies on sector models and a full field simulation model with dual porosity media and improved black oil options.
Combination of drive mechanisms acting in this field such as gas gravity drainage, diffusion and convection were represented. Various redevelopment options studied indicate that the overall oil recovery can be improved by gas injection pattern improvement and selected infill drilling with proper completion strategy.