Growth Mechanisms of Small-Displacement Strike–Slip Faults in Cratonic Basins: Insights from Material Point Method Simulations

Exploration in the Tarim Craton has established that small-displacement strike–slip faults control carbonate reservoirs’ development and oil and gas accumulation. Oil and gas primarily accumulate within a defined lateral distance from these faults. Material point method (MPM) simulations of such fault systems revealed a functional relationship between the regular spacing of initial oblique Riedel fractures and brittle layer thickness under simple shear. This thickness critically governs the spatial organization of the resultant fault system. Riedel shear zones propagate upwards from the base in a semi-elliptical pattern, producing fewer, but longer, shear zones with increasing brittle layer thickness. Stratum thickness exerts a first-order control on fault configuration during strike-slip deformation, modulating both fault segmentation patterns and interconnectivity. Key quantitative relationships emerged: (1) an inverse proportionality between stratum thickness and Riedel shear zone density and (2) a positive correlation between shear zone length and stratum thickness. This article provides experimental evidence and theoretical guidance for exploring deep-seated strike-slip faults in cratonic basins.