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Numerous volcanic–sedimentary rocks of the Wanquan and Gaiyang groups are found throughout the Nanping–Ninghua tectonic belt, South China. However, detailed studies on the tectonic evolution of the Nanping–Ninghua tectonic belt have been limited by the lack of systematic previous research linking these volcanic–sedimentary rocks. This study presents a systematic petrological, geochronological, and geochemical study of meta‐volcanic rocks from the Louqian Formation in Mingxi County, China. Zircons from these rocks were analysed by laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) and yielded a U–Pb weighted mean age of 734.7 ± 3.3 Ma. The SiO2 contents of the meta‐volcanic rocks range from 59.91 to 73.47 wt.%, and they have high Al2O3 and Na2O + K2O contents (13.17–18.80 and 6.73–11.19 wt.%, respectively), and low CaO, MgO, and FeOT contents. All samples are enriched in large‐ion lithophile elements (LILE; e.g., Ba, Rb, and K) and depleted in high‐field‐strength elements (HFSE; e.g., Nb, Ta, Ti, and P). Marked negative Eu anomalies are similar to those in arc igneous rocks. Based on regional geological data and previous studies, we propose that the Nanping–Ninghua tectonic belt formed in an active continental margin environment from 825 to 696 Ma. Island arc magmatism was caused by the oceanic crust subduction, which contributed to the formation of an intermediate–silicic volcanic belt along the Nanping–Ninghua continental margin that was active until 696 Ma. The North and South Wuyi blocks did not assembly to form a unified Wuyi Block before 696 Ma, and there is no unified pre‐Nanhua crystalline basement present in the Cathaysia Block.

Zircons from two samples of the Sukeng pluton in the southwest Fujian Province, China, were analyzed by LA-ICP-MS with the aim of determining the timing of formation. The zircons from the two samples yield similar U-Pb ages of 100.47 ± 0.42 and 102.46 ± 0.69 Ma, indicating that the Sufeng pluton is contemporaneous with the Sifang and Luoboling plutons, all of which are also related to Cu-Au-Pb-Zn-Mo mineralization within the study area. All three plutons have geochemical features of I-type granites, are high-to mid-K calc-alkaline metaluminous rocks, and have average molar Al 2 O 3 / (CaO+Na 2 O+K 2 O) values of 0.95, initial 87 Sr/ 86 Sr ratios of 0.70465-0.70841, Nd(t) values at 101 Ma from -1.72 to -7.26, and two-stage Nd model ages (T 2DM ) from 1.16 to 1.60 Ga.Zircons within these plutons have Hf(t) values at 101 Ma from -3.5 to 6.25 and T 2DM ages from 0.74 to 1.46 Ga, suggesting these I-type granites formed from magmas generated by partial melting of Mesoproterozoic to Neoproterozoic continental crust that mixed with mantle-derived magmas. The magmatism was associated with thickening of the lower crust caused by collisions between microcontinents in the Cathaysian Block, which were driven by Early Cretaceous subduction of the Pacific Plate.

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