A Novel Three‐Dimensional Dynamic Fracture‐Modeling Method for Tight Reservoirs Integrating Focal Mechanism and Stress Field Constraints

ABSTRACT Tight oil and gas, as an important energy type, are produced in a way completely different from that of conventional oil and gas; their extraction must rely on hydraulic fracturing to create effective fracture networks and to enhance reservoir permeability. Therefore, research on fracture‐model structures is of great importance for the development of tight oil and gas. However, existing modeling methods based on microseismic data generally ignore differences in the mechanical properties of seismic sources, so the resulting fracture networks can hardly depict the true developmental azimuths and spatial morphologies of real fractures and are also unable to effectively distinguish different fracture planes. To solve this problem, this article proposes a three‐dimensional dynamic fracture‐modeling method that integrates focal‐mechanism solutions and stress‐direction constraints. First, P / T ‐axis parameters obtained from moment‐tensor decomposition are used to partition the hypocenters into regions, and the stress direction in each region is inverted. Then, by introducing stress‐direction constraints, primary and secondary fracture sources are identified, and a time‐evolving three‐dimensional fracture‐network model is constructed on the basis of penny‐shaped fracture planes. Field validation shows that the modeled fracture growth is synchronized with treatment‐pressure responses and that the fracture parameters extracted from the model are highly correlated with stage‐wise production, confirming the method's effectiveness and its engineering applicability. This method depends only on accurate microseismic event locations and moment‐tensor information; in principle, it is not limited by lithology and is therefore applicable to layered or non‐layered, monomineralic and polymineralic reservoir rocks.