Image Analysis of Proppant Performance in Pressurized Fractures

Abstract:

Proppants are small particles used to prop or hold open subsurface fractures to permit fluid flow through these pathways. In many oil and gas well applications, the most common proppant materials are sand, ceramic particles, resin-coated sands, glass beads or even walnut shells. More dense proppants require additives to create viscous fluids which can transport them further along wells and into fractures, but are generally preferred over neutrally buoyant options due to their increased strength. Currently, proppant strength and generation of broken fragments (“fines”) is analyzed via a standardized crush test between parallel plates. To augment this type of information, we present here the results of various experiments involving resin-coated proppants held at increasing pressures in fractured samples of Marcellus shale. The shale/proppant samples were imaged continuously with an industrial tomography scanner during pressurization up to 10,000psi. This technique allows for in situ characterization of fracture/proppant interactions and fracture void volume and average aperture with varying confining pressures.