Abstract
The topology of induced fractures by hydraulic fracturing is important for well performance in unconventional low-permeability reservoirs. Natural fractures are a common feature in geological formations and are preferred failure paths during hydraulic fracturing. Therefore, the interaction of hydraulic fractures and natural fractures is fundamental to the fracture growth in fractured reservoirs. Field observations of induced fracture systems show modeling fracture complexity to be needed for improving completion design and interpreting stimulated reservoir volume. In this study, a finite discrete-element model is presented to investigate multifracture propagation in fractured reservoirs. The numerical model captures the fracture complexity including branched, stranded, and kinked fractures, as well as offset crossing of natural fractures. The results show biased fracture growth in the fractured reservoir, which demonstrates the impacts of rock heterogeneity on multifracture propagation. This work also emphasizes the control of fluid partition at the wellbore and among the intersecting fractures. Fluid partition at the wellbore is found to be a major challenge to the completion design of tight cluster spacing, which has been shown to improve production in recent years.
NSTL