Abstract
Models of hydraulic fracture propagation in the hydrocarbon industry have been traditionally based on boundary element methods, finite difference method, and recently supplemented by peri-dynamic continuum formulations. These methods commonly require extensive gridding accompanied by elevated capital investments to acquire the target resolution. This study applies a recently developed semi-analytical method, which is fast and grid-less, to model fracture propagation due to crack-face loading and crack-tip stress concentrations. The Time-stepped Linear Superposition Method (TLSM) allows for the visualization and quantification of the dynamic propagation of multiple hydraulic and natural fractures, while preserving infinite resolution by sidestepping grid refinement. By visualizing stress concentrations and predicting fracture propagation paths, the dynamics of fracture hits and fracture redirection can be investigated. Solutions solved by TLSM are benchmarked against independent studies to ensure physical and practical compatibility. The insight of how growth of hydraulic fractures may deviate from planar model conceptions will be useful to optimize fracture treatment plans. TLSM is used to model dynamic solutions for typical zipper fracturing completions, showing the effect of well spacing, and fracture spacing on the development of fracture hits and fracture redirection.
Hydraulically fractured horizontal wells have been at the forefront of hydrocarbon production in tight shale. The common objective for any horizontal well completion technique is to maximize the fracture network surface area within the reservoir. High number of perforations, tighter fracture spacing, and tighter well spacing, have all been used to increase fracture-surface exposure to petroleum-bearing rocks. While maximizing fracture network contact with pay zone is the objective of a fracture treatment plan, due to stress shadow effects, lower number of perforations could be more beneficial in complex fracture network creation (Fisher et al., 2004). A higher number of clusters may contribute to higher completion cost, which needs justification, especially when oil prices are depressed. In addition, the effect of well interference is magnified when wells are tighter spaced, which may adversely impact production rates (Roussel and Sharma, 2011).
