Decoding the Middle Tonian Tectonic Evolution of the Jiangnan Orogen, South China: Integrated Constraints from Volcano-Sedimentary and Magmatic Records of the Fanjingshan Region

A comprehensive analysis of the Fanjingshan region reveals that the Middle Tonian tectonic evolution of the Jiangnan Orogen, South China, was driven by subduction and collision rather than a mantle plume. This conclusion is supported by integrated sediment provenance data from 1736 detrital zircon U-Pb ages and geochemical studies of coeval magmatic suites, including basalts, mafic–ultramafic sills, and granitoids. The study identifies a four-stage tectonic model: an early passive margin phase (pre-870 Ma), followed by continental arc development (870–835 Ma), collisional amalgamation (835–820 Ma), and post-orogenic rifting (post-820 Ma). Geochemical signatures, such as calc-alkaline affinities and subduction-fluid indicators in basalts, further corroborate the plate margin setting. This work underscores the importance of combining sedimentary and magmatic records to reconstruct ancient orogen evolution.

Dai, Y., Zhang, J., Ye, T., Zhang, T., Chen, J., & Shi, L. (2026). Decoding the Middle Tonian Tectonic Evolution of the Jiangnan Orogen, South China: Integrated Constraints from Volcano-Sedimentary and Magmatic Records of the Fanjingshan Region. Minerals, 16(3), 334. https://doi.org/10.3390/min16030334