Research on the construction method of complex fracture networks based on microseismic data

Three-dimensional simulation of fracture networks based on microseismic data from hydraulic fracturing is of significant importance and value for obtaining fracture development morphology, studying fracture characteristics, and evaluating fracturing production. It not only helps to understand the development of fractures but also provides references for subsequent fracturing operations. However, existing methods for simulating fracture networks based on microseismic data mainly rely on spatiotemporal clustering analysis of hypocenter locations, which lack theoretical support, leading to unreliable fracture network structures. To address this issue, this paper proposes an innovative method for fracture network modeling. The method first conducts cluster analysis based on the P-axis direction of the hypocenters, dividing the seismic data into different clusters and performing regional stress inversion to determine the principal stress direction of each cluster, which is assumed to be the direction of fracture development. Then, an improved Random Sample Consensus algorithm is used to identify co-planar hypocenters along the direction of fracture development. For hypocenters not identified as co-planar, a fractal dimension method is employed to fit the fracture surfaces. Finally, the new three-dimensional modeling algorithm is used to construct the fracture model. This method has been validated with multiple sets of measured microseismic data, and the results show that it has high accuracy and reliability in predicting fracture development direction, guiding and optimizing fracturing construction plans, calculating effective fracture volume, and predicting oil and gas production capacity. It provides a new method and perspective for understanding the development of hydraulic fracturing reservoirs and evaluating the effects of oil and gas production capacity.