In the Permian basin, unconventional reservoirs have been the main target of horizontal well drilling since the early 2000s. Over the years, completion design in horizontal wells has evolved from conservative to radical designs. The main purpose of this paper is to evaluate different completion and stimulation design scenarios to understand their impact on hydraulic fracture geometry and production performance. This paper is an extension of a previous work presented by Ajisafe et al. at the 2016 SPE Hydraulic Fracturing Technology Conference (SPE-179130-MS) on the use of discrete fracture network from seismic data for complex fracture modeling.
In most unconventional plays, the existence and interaction of the discrete fracture network (DFN) and hydraulic fractures during a stimulation treatment creates a complex fracture geometry. In the present study, seismic data provided an improved DFN model along and particularly away from the wellbore. The microseismic events showed variation in hydraulic fracture complexity and geometry along the lateral of the subject horizontal well.
A multidisciplinary integrated workflow was applied to the horizontal well to model complex hydraulic fractures and production. The DFN model and geomechanical properties were key inputs into the unconventional fracture model (UFM) and were constrained with the microseismic data and production history. After the UFM model was created, different sensitivity categories such as proppant job size, cluster spacing, and maximum proppant concentration, were investigated for their impact on the complex fracture geometry as well as production performance.
The field is an expensive laboratory. The use of advanced hydraulic fracture and reservoir simulation models can help provide the best completion design options from the start of field development as opposed to executing multiple field tests to determine the optimal design. The optimal completion design to increase hydrocarbon production with proper economics evaluation is critical for maximized returns. Single-well optimization is an important step in the unconventional workflow, and ultimately for better planning of multi well pad and infill well development.