This study investigates the provenance of the Permian Shihezi Formation (Fm) siliciclastic sediments in the Luonan area, southern margin of the North China Block, which constrain the sediment sources and tectonic evolution of the basin. Our research investigates the heavy mineral characteristics, geochemical features, detrital zircon U-Pb geochronology, and Lu-Hf isotope tracing the provenance characteristics of the Shihezi Fm in this region. Zircon yielded three distinct U-Pb age groups as follows: 320–300 Ma, 1950–1850 Ma, and 2550–2450 Ma. The ε_Hf(t) values of zircons ranged from −41 to 50, and the two–stage Hf model’s ages (T_DM2) values are concentrated between 3940 Ma and 409 Ma, suggesting that magmatic sources likely derive from Early Archaean–Devonian crustal materials. The heavy mineral assemblages are primarily composed of zircon, leucoxene, and magnetite. Further geochemical analyses of the rocks indicate a diverse provenance area and a complex tectonic evolution. Taken together, these results suggest that the provenance of the Shihezi Fm is from the North China Block, with secondary contributions from the Qinling Orogenic Belt and the North Qilian Orogenic Belt. The provenance of Luonan shares similarities with the southern Ordos Basin. Investigating the provenance of the Luonan area along the southern margin of the North China Craton provides critical supplementary constraints for shedding light on the Late Paleozoic tectonothermal events in the Qinling Orogenic Belt.

This study takes the Jiangligou Plutonic Complex (JPC) in the Western Qinling tectonic belt as the research object and systematically investigates the crystallization age, magmatic genesis, and tectonic setting of the plutons. Results indicate that the Jiangligou Plutonic Complex was formed during the Triassic period (252–216 Ma, corresponding to the “Indosinian” regional tectonic stage in East Asia). Six plutons are recognized in the Jiangligou region. Plutons IV (246 ± 3 Ma) and V (252 ± 2 Ma) record Early Triassic magmatism, and Plutons I (238 ± 1 Ma), II (216 ± 2 Ma), III (216 ± 2 Ma), and VI (224 ± 2 Ma) correspond to Middle-Late Triassic magmatic activity. Furthermore, the data from this study indicate that a Th/U ratio > 0.4 serves as a more effective criterion for identifying reliable magmatic zircons. Our data indicate that the Jiangligou Plutonic Complex represents a multi-stage magmatic system generated in response to the tectonic evolution of the West Qinling, spanning from the late subduction of the Mianlue Ocean to the peak collision between the North China and Yangtze blocks during the Indosinian orogeny. The region is dominated by a collisional setting, with magmas primarily derived from crustal remelting. This study provides key chronological and geochemical constraints on the Indosinian tectonic–magmatic evolution of West Qinling.

The provenance of the Middle-Upper Permian in the Lintan and Jiangligou areas, remnants of rift basin sedimentation within the West Qinling, remains controversial, hindering understanding of the basin-range coupling evolution of the Qinling Orogenic Belt and its periphery. Heavy minerals, major and trace elements, rare earth elements, detrital zircon U-Pb dating, and in situ Lu-Hf isotopes were analyzed to determine the provenance of the Middle-Upper Permian sandstones. Results were integrated with previous studies to investigate basin-range coupling processes. The results reveal the following: (1) The Upper Member of the Shilidun Formation in the Lintan area was deposited during the Late Permian. Heavy minerals are dominated by moderately to highly stable species. Source rocks were derived from intermediate-acidic magmatic rocks and low- to medium-grade metamorphic terrains. The provenance was primarily situated in a continental island arc tectonic setting. Diverse source rock types were identified, including materials from felsic igneous, quartzose recycled, and mafic igneous provenances. Detrital zircon U–Pb age spectra display two major peak ages at 285 Ma and 442 Ma, along with five subordinate peaks at 818 Ma, 970 Ma, 1734 Ma, 1956 Ma, and 2500 Ma. The ε_Hf(t) values range from –44.95 to 42.67, and T_DM2 ages vary from 367 Ma to 4106 Ma. It is concluded that the sedimentary materials were mainly derived from the North Qinling Orogenic Belt, with minor contributions from the basement of the North China Craton. (2) In the Jiangligou area, the Shiguan Formation is characterized by highly and stable heavy minerals. The provenance is dominated by intermediate-acidic magmatic rocks, within an oceanic island arc tectonic setting. Detrital zircon U–Pb age spectrum displays a prominent peak at 442 Ma. The ε_Hf(t) values range from –0.5 to 10.55, with T_DM2 ages ranging from 744 Ma to 897 Ma. These results indicate that the sedimentary materials were derived from the North Qilian Orogenic Belt. (3) The Permian in the Western Qinling exhibit multi-provenance supply, dominated by the North Qinling Orogenic Belt and the North China Craton basement, with local contributions from the North Qilian Orogenic Belt. Significant regional variations in provenance contributions were identified. This study further constrains the closure of the Shangdan Ocean to pre-Late Permian. It reveals that the Western Qinling was situated in a back-arc rift basin setting during the Late Paleozoic. Key sedimentary evidence is provided for understanding the tectonic evolution of the Paleo-Tethys Ocean and the collision between the North China and Yangtze cratons.