Study on proppant embedment in rough fracture surface based on three dimension laser scanning

Abstract

In formation, fracture surfaces are rough and proppant embedment is complex. However, when conducting proppant embedding experiments, most researchers assume a smooth fracture surface, which does not accurately reflect the real fracture. As a result, the rough fracture surface is scanned by three dimension (3D) laser to reconstruct the rough fracture based on the point data in this paper, which established a “proppant - rough fracture” contact model based on finite element theory, analyzed the influence (the closure stress and young's modulus of proppant, proppant size, the elastic modulus of proppant and rock) of embedment depth in the rough fracture. Numerical simulation results show that the embedment depth of the proppant increases with the increase of closure stress. The embedment depth of proppant on rough fracture surface increases with the increase of proppant elastic modulus but decreases with the increase of rock's elastic modulus. The embedment depth of the proppant in the rough fracture is smaller than that in a smooth plate under the same closure stress. To ensure the consistency, repeatability, and accuracy of the rough fracture surface, it was analyzed using reverse reconstruction. This study can be used as a simple method to investigate the rule of proppant embedment in rough fracture surfaces to provide a reference and basis for hydraulic fracturing in the oilfield.