Duration of the Huangling Dome Activity in the Northern Margin of the South China Continent: Insight From Integration of Zircon (U–Th)/He Dating and Thermal Modeling

Abstract

The South China continent was extensively deformed during the Mesozoic, in response to complex convergence between the neighboring plates in East Asia (Figure 1a). This tempo-spatial variation of convergence-related contraction is responsible for many tectonic domes formed in the reactivated continent (S. Z. Li et al., 2017;Zheng & Shan, 2020). Among them, one of the largest tectonic domes is the ca. 70 × 100 km 2 , oval-shaped Huangling dome in the northern margin (Figure 1b). This ∼N-S trending dome lies between the ∼E-W-trending fold-and-thrust belts to the north and south. Both the platform cover and the underlying crystalline basement were involved in the dome formation, making up a >12 km-thick folded layer (Zheng, 2021). In general, the basement exhumed in the dome core has undergone brittle deformation characterized by faults and joints formed since the Mesozoic (Ji et al., 2014;Zheng & Shan, 2020). For these reasons, determining when and how the dome was developed sheds new light on the complex deformational history of the continental interior during tectonic reactivation.