Acoustic Emission and Features of Hydraulic Fracture Propagation in Heterogeneous Model Materials
摘要
The paper presents the results of laboratory investigations of hydraulic fracturing in specimens made of a model material. Acoustic emission (AE) was monitored and the parameters of the hydraulic fracture were measured in samples with different proppants. It is shown that the formation of the hydraulic fracture is accompanied by a sharp burst of AE activity, and that its initiation occurs in the vicinity of the maximum injection pressure. The main fracture had a branched shape (two or three branches), depending on the experimental conditions. Spectral analysis of the AE signals and source localization were carried out, demonstrating the influence of the proppant material (marble, gravel) on the characteristics of the acoustic signals.