The most common completion methodology the industry uses to help maximize productivity and fluid recovery in unconventional reservoirs consists of placing multiple, optimally spaced transverse fractures in horizontal wells, navigating along the direction of minimum principle horizontal stress. In this type of completion, well productivity and fluid recovery can be maximized when the following conditions are met:
Horizontal wellbore navigates optimally in the reservoir.
Generated fracture connects the entire productive pay zone.
Transverse fractures are optimally spaced.
Proppant is well-distributed throughout the created fracture.
With respect to the actual completion strategy, the first two conditions are met using proper geological interpretation and measurements of fracture height growth (e.g., microseismic); the third condition depends on economics and cluster efficiency. However, the distribution of proppant within the hydraulic fractures is usually ignored, particularly for cases in which low-viscosity fracturing fluids are used for stimulation.
By performing extensive simulations for gas-producing reservoirs with a wide range of unconventional reservoir permeabilities, this paper quantifies the impact of proppant distribution on well productivity and the recovery factor (RF). For cases in which proppant distribution is not optimized, previously published extensive simulations demonstrate that the RF and productivity are significantly affected.