Structural features and evolution of the multi-stage tectonic deformation in the southwestern Tarim Basin (China): insights from discrete numerical simulations

Cai Chen, Wenqiao Xu, Jiuzhou Chen, Zihan Gao, Jie Yang, Hongwei Yin, Haoyue Zheng, J. H.

The southwestern Tarim Basin records a complex Mesozoic–Cenozoic polyphase tectonic evolution characterized by three distinct stages: Late Triassic compression, Jurassic–Late Cretaceous extension, and Miocene–present compression. However, the kinematic mechanisms governing deformation inheritance, mechanical stratigraphy, and syn-tectonic sedimentary feedback remain insufficiently understood. Here we integrate seismic interpretation, balanced cross-section restoration, and discrete element method simulations to investigate the multi-stage evolution of the SW Tarim fold-and-thrust belt. Our results demonstrate that deformation is dominated by repeated reactivation of pre-existing faults, indicating strong kinematic inheritance. Mechanical stratigraphy, particularly Cambrian evaporites and Paleogene gypsum–mudstone layers, controls vertical decoupling and limits fault propagation. Syn-tectonic sedimentation modulates deformation through differential loading and accommodation space infill, influencing strain localization, fault propagation, and growth strata development. The tectonic cycle governs the coupled evolution of source rocks, reservoirs, and seals, with early compression forming traps, extension enhancing migration pathways, and Cenozoic compression improving trap integrity and burial conditions. These results highlight the coupled roles of kinematic inheritance, mechanical stratigraphy, and syn-tectonic sedimentation in shaping fold-and-thrust systems and provide new insights for hydrocarbon exploration in complex foreland basins.