This paper presents a new workflow comprised of using hydraulic fracture modeling outputs (effective length, height, and conductivity) for the next step - a discrete fracture flow model which visualizes the drainage pattern in 3D based on history matched production data.
The first part of the paper is designated to fracture forward modeling and prediction of the proppant placement geometry and conductivity of hydraulic fractures in a multistage horizontal well. The influence of wellbore deviations and other local initial conditions are all taken into account and explain localized fracture initiation, fracture asymmetry, and propagation, as well as proppant placement efficiency. The primary model focus is on the creation of fracture conductivity maps, one for each transverse fracture.
The second part of this study shows the process of import and conversion of 2D fracture conductivity maps for further use in fluid flow allocation to the individual fractures. The 3D Drained Rock Volume (DRV) is rendered based on 2D streamline and time-of-flight maps for drainage, velocity and pressure depletion with 5 ft vertical resolution layers representing the reservoir. Instead of using a grid-based numerical simulation, we apply a meshless flow model based on Complex Analysis Methods (CAM) to solve linear differential equations. The fluid velocity field is computed for narrowly discretized time steps, which allows high-resolution visualization of hydrocarbon flow near and into each of the discrete fractures.
Honoring critical physical interaction of fracture fluid, rock mechanics, proppant transport, the fracture propagation model coupled with the flow model for discrete fractures, provides a powerful tool to pinpoint the drained rock volume. Our systematic study highlights trade-offs between fracture design inputs and the total drained rock volume. Field data from the Wolfcamp Formation, Midland Basin in West Texas, provides a real-world case to demonstrate our workflow. Recommendations are made for adjusting frac design and improving the recovery factor of hydrocarbons in place.