Relationship between Lateral/Basal Shear Stress Ratio and Structural Vergence of Thrust Wedges: Results from Analogue Modeling and Implications for the Origin of Eastern Sichuan–Xuefeng Fold?Thrust Belt in South China

Thrust wedges are common in nature, but not all of their origins can be properly explained by the classic Coulomb wedge theory, which considers only a 2D perspective. A few analogue models, however, revealed that lateral shear stress (inherent both models and nature) may strongly affect development thrust lateral/basal (?s/?d) ratio might have controlled structural vergence wedge, suggesting origin needs to considered from 3D The Eastern Sichuan–Xuefeng fold-thrust belt (ESXFTB), is characterized two oppositely vergent systems at different crustal levels contain another large purely backward-vergent on world, still problematic. Revealing relationship between ?s/?d prompt deep understanding as well ESXFTB. This relationship, very clear due lack systematic experiments. For these reasons, we performed experiments types under ratios. Our model results revealed, for first time, lying weak décollement progressively change frontward (when <0.09) dual = 0.09–1.15) then backward >1.15) ESXFTB produced simultaneously single northwestward Mesozoic shortening probably apparently