Granite Emplacement in a Transpressional Tectonic Setting: Evidence of the Intra‐Pangea Megashear in Eastern China

Abstract Understanding the mechanisms of pluton emplacement is crucial for elucidating the interaction between regional tectonics and magmatism. Tension gashes and pull‐apart structures play an important role in the plutonic intrusion in extensional and transtensional tectonics. However, the emplacement mechanisms in transpressional settings remain not fully constrained. A multidisciplinary study including structural analysis, anisotropy of magnetic susceptibility (AMS), gravity modeling, and zircon U‐Pb dating was conducted on the Triassic Yunwushan pluton in the North China Craton (NCC). Geochronological results reveal that two stages of emplacement are distinguished: the early‐stage intrusion formed the northern and southern parts of the pluton (238–236 Ma), while the late stage constituted the central part of the pluton (233–232 Ma). Structural analyses indicate that, from interior to margins, the Yunwushan pluton shows transitions from magmatic to sub‐magmatic microstructures. The northern and southern parts are characterized by steeply dipping magnetic foliations and sub‐horizontal magnetic lineations that strike ENE‐WSW or E‐W. The central part is marked by magnetic foliations concentrated along a NE‐SW strike exhibiting a steep dip and sub‐vertical magnetic lineations. The gravity modeling reveals NW‐SE directed root structures interpreted as feeder zones opened by regional transpression. The Yunwushan pluton is considered to be emplaced in a transpressional setting in which magma can ascend through “en‐échelon” fractures, which are oblique to strike‐slip shear zones. Based on these new data and regional tectonics, the Yunwushan pluton was emplaced in the late stage of the strike‐slip tectonics, which may represent the easternmost part of the Intra‐Pangea Megashear.