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This study presents new detrital zircon laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) U–Pb ages and in situ Hf–O isotopic data in order to constrain the depositional age and provenance of the Benxi Formation in the Sanmenxia area of the southern North China Craton (NCC). Detrital zircons in quartz sandstone drillcore from the Benxi Formation are euhedral–subhedral, oscillatory zoned, and have high Th/U ratios (0.03–1.60, generally greater than 0.3) that are indicative of a magmatic origin. Detrital zircons from samples 13H16A and 13H16B yield seven (2544, 1788, 1123, 955, 737, 441, and 344 Ma) and six main age populations (2440, 1583, 951, 759, 434, and 348 Ma), respectively. The εHf(t) values of the Neoarchean–Paleoproterozoic zircons range from −11.3 to +13.9, and these zircons have δ18O values that range from 5.68‰ to 8.83‰. The Neoproterozoic zircons have variable εHf(t) (−9.2 to +12.5) and δ18O (5.58‰ to 9.85‰) values, whereas the Palaeozoic zircons have εHf(t) values between −19.9 and +13.4 and δ18O values of 5.23‰–9.43‰. The Benxi Formation was deposited during the late Carboniferous and contains sediments derived from igneous rocks of the North Qinling Orogen combined with a small amount of material derived from Precambrian basement of the NCC. The northward subduction of the South Qinling Orogen caused the uplift and erosion of the North Qinling Orogen during the late Carboniferous. [ABSTRACT FROM AUTHOR]

With the aim of constraining the influence of the surrounding plates on the Late Paleozoic–Mesozoic paleogeographic and tectonic evolution of the southern North China Craton (NCC), we undertook new U–Pb and Hf isotope data for detrital zircons obtained from ten samples of upper Paleozoic to Mesozoic sediments in the Luoyang Basin and Dengfeng area. Samples of upper Paleozoic to Mesozoic strata were obtained from the Taiyuan, Xiashihezi, Shangshihezi, Shiqianfeng, Ermaying, Shangyoufangzhuang, Upper Jurassic unnamed, and Lower Cretaceous unnamed formations (from oldest to youngest). On the basis of the youngest zircon ages, combined with the age-diagnostic fossils, and volcanic interlayer, we propose that the Taiyuan Formation (youngest zircon age of 439 Ma) formed during the Late Carboniferous and Early Permian, the Xiashihezi Formation (276 Ma) during the Early Permian, the Shangshihezi (376 Ma) and Shiqianfeng (279 Ma) formations during the Middle–Late Permian, the Ermaying Group (232 Ma) and Shangyoufangzhuang Formation (230 and 210 Ma) during the Late Triassic, the Jurassic unnamed formation (154 Ma) during the Late Jurassic, and the Cretaceous unnamed formation (158 Ma) during the Early Cretaceous. These results, together with previously published data, indicate that: (1) Upper Carboniferous–Lower Permian sandstones were sourced from the Northern Qinling Orogen (NQO); (2) Lower Permian sandstones were formed mainly from material derived from the Yinshan–Yanshan Orogenic Belt (YYOB) on the northern margin of the NCC with only minor material from the NQO; (3) Middle–Upper Permian sandstones were derived primarily from the NQO, with only a small contribution from the YYOB; (4) Upper Triassic sandstones were sourced mainly from the YYOB and contain only minor amounts of material from the NQO; (5) Upper Jurassic sandstones were derived from material sourced from the NQO; and (6) Lower Cretaceous conglomerate was formed mainly from recycled earlier detritus. The provenance shift in the Upper Carboniferous–Mesozoic sediments within the study area indicates that the YYOB was strongly uplifted twice, first in relation to subduction of the Paleo-Asian Ocean Plate beneath the northern margin of the NCC during the Early Permian, and subsequently in relation to collision between the southern Mongolian Plate and the northern margin of the NCC during the Late Triassic. The three episodes of tectonic uplift of the NQO were probably related to collision between the North and South Qinling terranes, northward subduction of the Mianlue Ocean Plate, and collision between the Yangtze Craton and the southern margin of the NCC during the Late Carboniferous–Early Permian, Middle–Late Permian, and Late Jurassic, respectively. The southern margin of the central NCC was rapidly uplifted and eroded during the Early Cretaceous. [ABSTRACT FROM AUTHOR]