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It is unclear whether the South China blocks have an affinity with continental Gondwana due to a lack of direct Pan‐African magmatic and metamorphic features. In this study, we conducted U‐Pb geochronological and Lu‐Hf isotopic analyses for detrital zircons from a sandstone of the Chang'an Formation of the Nanhua Group in the Longsheng region of northern Guangxi, with the aim of constraining the timing of sedimentation and information as to its source, as well as seeking evidence for Pan‐African events in the South China blocks. The results show that the ages of detrital zircons peaked at 654.7 ± 6.2 Ma, 773.2 ± 4.1 Ma and 821.9 ± 6.5 Ma, with some at 920–870 Ma; the youngest age indicates the existence of the Pan‐African thermal event. The ∊Hf(t) and TDM2 values demonstrate that the study area has experienced three stages of crustal growth at 3.0–2.4 Ga, 2.1–1.5 Ga and 1.3–0.9 Ga. With intensively distributed Neoproterozoic mafic‐ultramafic and granitic plutons emplaced at 830–810 Ma along the southwestern section of the Jiangnan Orogenic Belt and positive ∊Hf(t) values from a large group of zircon grains, it is proposed that the sediments of the Chang'an Formation (of Nanhua Group) were largely sourced from the southeastern margin of the Yangtze block. Comparison with the zircon age spectra of the Cathaysian block shows that about 79% of the Pan‐African aged detrital zircon grains that have TDM2 = 1352–1031 Ma and ∊Hf(t) = 3.68–8.79, were sourced from the recycled Grenvillian crust of the Cathaysian block, suggesting that the Cathaysian block had a close connection with Gondwana.

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Recognition of deformation events documented in Neoproterozoic sedimentary sequences of the Jiangnan Orogen is critical in understanding the tectonic evolution of South China. In this contribution, we present new field based structural observations, microstructural analysis, and geochronological data for the Sibao and Danzhou groups in the southwestern Jiangnan Orogen of northern Guangxi, South China. Integrating the new information with previously published structural and geochronological data, we have identified three major deformation events. The earliest event generated E-W-trending high-angle tight linear and overturned isoclinal folds in the Sibao Group with their fold axial planes dipping to the south. This shortening event occurred in the mid-Neoproterozoic time (840-800 Ma) and was associated with the orogenic collision between the Yangtze and Cathaysian blocks in South China. The angular unconformity between Sibao and Danzhou groups provides strong evidence for the collision. The second deformation event produced the large-scale NNE-SSW-striking ductile shear zones in the region. It also overprinted the preexisting E-W-trending folds, refolded the Sibao Group, and generated the large-scale NNE-SSW-trending open folds in the overlying Danzhou Group and the westdipping cleavage within both groups. The second event occurred during the early Palaeozoic time (460-410 Ma) as a result of a WNW-ESE-oriented intracontinental shortening process. The latest deformation event generated slight crenulation cleavage in the Sibao Group, some folds in the marble units of the Danzhou Group, and normal-sense shearing along the pre-existing NNE-SSW-striking shear zones, all of which are the result of a NW-SE-directed crustal extension during the late Palaeozoic (410-350 Ma) Kwangsian (Caledonian) orogenic collapse.