Crustal structure and formation mechanism of the fold-and-thrust belt in and around Wuling mountains region

The Wuling fold−and−thrust belt, located along the eastern margin of the Yangtze block, is a significant linear tectonic belt shaped by the intra−continental compressional forces in South China. Understanding its formation mechanisms is crucial for advancing broader tectonic evolution of the region. This study examines the deep crustal architecture, deformation processes, and surface tectonics within the Wuling fold−and−thrust belt by integrating high−resolution geophysical imaging, detailed tectonic analysis, and recent numerical and analog modeling. The key findings are as follows: ① The pronounced gravity gradient belt across the Wuling Mountains is primarily controlled by structural and compositional variations at the crustal and lithospheric levels; ② The Neoproterozoic collision and subsequent amalgamation of the Yangtze and Cathaysia blocks shaped the crustal structure, leading to the Moho undulation, break−off, imbrication, and other related features; ③ A low−velocity décollement layer, in combination with pre−existing regional faults, facilitated crustal decoupling and played a critical role in the structural evolution of the belt; ④ Far−field stresses from Paleo−Pacific plate subduction during the Late Mesozoic were the primary drivers of the observed fold−and−thrust deformation. These findings may offer new insights into knowledge on the intra−continental deformation mechanisms in South China and also contribute to refining tectonic models in other similar regions.