Numerical investigation of single and multiple fractures propagation in naturally fractured reservoirs

The properties of natural fractures (NFs), including fracture size, aperture width, and mechanical properties, etc., cannot be neglected when developing a model of hydraulic fracturing. Without considering the geological characterisation of NF properties, hydraulic fracture simulations will give much less accurate prediction of complex fracture propagation pattern. In this research, a novel two-dimensional finite-discrete element method (FDEM) model has been developed to describe complex fracture propagation in unconventional formations. We developed a natural fracture network builder by considering natural fractures geological observations. Simulations have been conducted to investigate single fracture and complex fracture network propagation in naturally fractured reservoirs. In hydraulic fracturing treatments, opening of natural fractures is determined by geological properties of NFs. For multiple fractures propagation in naturally fractured reservoirs, stress shadowing effect plays a key role in fracture network evolution. This work provides a framework for more realistic prediction of complex fracture geometry in naturally fractured formations. [Received: December 11, 2017; Accepted: July 6, 2018]