Evaluation of PFC 2D for Modeling Seismic Monitoring of Hydraulic Fracture

Abstract

Hydraulic fracture monitoring is a technique used for determining the geometry of the fracture underground. Active methods of fracture monitoring have shown potential in providing useful information which may not be easily obtained by microseismic methods. In this study Particle Flow Code in Two Dimensions (PFC2D), a Discrete Element Method (DEM) based code, is used for modeling seismic monitoring of a hydraulic fracture. PFC capability in modeling wave propagation in arranged particle assemblies is examined against another verified code. Furthermore, a smooth hydraulic fracture is generated by simulating constant fluid pressure source at the center of the sample. Seismic waves are transmitted across the fracture at different instances before and during fracture propagation. The results show that the width and length of the hydraulic fracture considerably influence the travel time and the amplitude of recorded waves even before the fracture reaches the source-receiver line. This is in accordance with published experimental results.