Proppant transport in complex fracture networks – A review

Abstract

Hydraulic fracturing in shale resources often result in complex fracture networks due to the presence of natural fractures, bedding planes and/or low deviatoric in situ stress. Fracture treatments with low-viscosity slickwater are commonly used as a completion technique in the shale reservoirs which show poor proppant transport characteristics as well as rapid proppant settling. Understanding proppant transport in complex fracture networks play a critical role in estimating propped fracture dimensions and reducing uncertainty in well drainage estimation. This paper presents a comprehensive review of several laboratory and numerical simulation studies which have been carried out over the past decade to evaluate proppant transport in the complex fracture networks. A better understanding of proppant movement in fracture networks with subsidiary fractures can help with optimizing fracture treatment designs and understanding what impact this transport may have on resulting production. Furthermore, understanding proppant transport in these fracture networks can help with re-frac candidate selection and enhanced oil recovery feasibility.