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A-type granite shows unique geochemical characteristics and refers to specific formation conditions and tectonic environments, and therefore plays an important role in reconstructing orogenic events. In this paper, we systematically investigated the zircon U Pb, whole-rock geochemistry, in-situ zircon Hf, apatite trace elements, and in-situ Nd data of the Huanren monzogranite to discuss its petrogenesis and the tectonic evolution of Jiao-Li-Ji belt. The studied zircon and apatite grains show typical oscillatory zoning and subhedral texture as well as obvious internal structure without any fluid/mineral inclusions, referring to a magmatic origin. Therefore, zircon U Pb dating results suggest that the Huanren monzogranite was formed in the late Paleoproterozoic (1863–1842 Ma). The studied rocks show typical A-type granite affinities as high SiO 2 (64.54–69.06 wt%), Na 2 O + K 2 O (8.00–9.34 wt%), and Zr + Nb + Ce + Y (381–598 ppm) concentrations, and FeOT/(FeOT + MgO) (0.82–0.85) and 10000Ga/Al (2.37–2.65) ratios. Their high whole-rock Zr temperature (812–866 °C, generally >840 °C), and low whole-rock Sr (109–157 ppm), apatite Sr (43.4–79.3 ppm) contents, whole-rock Sr/Y (4.79–8.22) and apatite Sr/Y (0.014–0.033) ratios, combined with slightly depleted in-situ zircon Hf (−1.62 to +2.50) and in-situ apatite Nd (−3.22 to −1.65) isotopic compositions, and ancient zircon Hf two-stage model ages (T DM2 ; 2606–2351 Ma), apatite Nd-T DM2 (2576–2451 Ma), suggest that the studied rocks were formed by partial melting of Neoarchean to Paleoproterozoic granitic gneiss in a high temperature and low-pressure condition. The studied A-type granite, together with regional A-type granite and alkaline syenite in the North China Craton, record the post-collisional event between the Nangrim and Longgang blocks, which combined with coeval worldwide A-type granite magmatisms, representing a response of the initial breakup of Columbia supercontinent. [Display omitted] • The studied granite was emplaced at 1.86–1.84 Ga and showed an affinity of aluminous A-type granite. • The reworking of ancient granitic gneiss occurred in a post-collisional environment. • The worldwide coeval A-type granites recorded the initial breakup of the Columbia supercontinent. [ABSTRACT FROM AUTHOR]

Abstract This paper reports geochronological, geochemical, zircon U–Pb and Hf–O isotopic data of the Late Triassic and Early Jurassic intrusive rocks in the northeastern North China Craton (NCC), with the aim of reconstructing the tectonic evolution and constraining the spatial–temporal extent of multiple tectonic regimes during the early Mesozoic. Zircon U–Pb ages indicate that the early Mesozoic magmatism in the northeastern NCC can be subdivided into two stages: Late Triassic (221–219 Ma) and Early Jurassic (180–177 Ma). Late Triassic magmatism produced mainly granodiorite and monzogranite, which occur as a NE–SW-trending belt parallel to the Sulu–Jingji Belt. Geochemically, they are classified as high-K calc-alkaline and metaluminous to weakly peraluminous granitoids, and are enriched in large-ion lithophile elements (LILEs) and light rare earth elements (LREEs), and depleted in high-field-strength elements (HFSEs; e.g., Nb, Ta, Ti, and P) and heavy rare earth elements (HREEs), indicating an affinity to adakite. Combined with their ε Hf (t) values (−17.9 to −3.2) and two-stage model ages (2387–1459 Ma), we conclude that the Late Triassic granitoid magma in the northeastern NCC was derived from partial melting of the thickened lower crust of the NCC and was related to deep subduction and collision between the NCC and the Yangtze Craton (YC). The Early Jurassic magmatism is composed mainly of monzogranites, which are classified as metaluminous, high-K calc-alkaline, and I-type granite. Their ε Hf (t) values and two-stage model ages are −16.7 to −4.2 and 2282–1491 Ma, respectively. Compared with the Late Triassic granitoids, the Early Jurassic granitoids have relatively high HREE contents, similar to calc-alkaline igneous rocks in an active continental margin setting. These Early Jurassic granitoids, together with the coeval calc-alkaline volcanic rocks and gabbro–diorite–granodiorite association in the northeastern (NE) Asian continental margin, comprise a NNE–SSW-trending belt parallel to the NE Asian continental margin, indicative of the onset of Paleo-Pacific Plate subduction beneath Eurasia. Graphical abstract Unlabelled Image Highlights • Late Triassic and Early Jurassic magmatism is recognized in the northeastern NCC. • Late Triassic granites formed in an extensional setting related to the Su-Lu belt. • Early Jurassic magmatism marks the onset of the Paleo-Pacific Plate subduction. [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]

This paper reports new whole-rock geochemical, Sr–Nd–Pb isotopic, and zircon U–Pb and Hf isotopic data for Early Cretaceous intrusive rocks in the Sanmenxia–Houma area of central China, and uses these data to constrain the petrogenesis of low-Mg adakitic rocks (LMAR) and the spatial extent of the influence of the deeply subducted Yangtze slab during the Triassic evolution of this region. New zircon laser-ablation inductivity coupled plasma mass spectrometry (LA-ICP-MS) U–Pb data indicate that the early- and late-stage southern Quli, Qiligou, and Gaomiao porphyritic quartz diorites, the Canfang granodiorite, and the northern Wangmao porphyritic quartz monzodiorite were emplaced during the Early Cretaceous (~ 130 Ma) and the late Early Cretaceous (~ 116 Ma). These rocks are characterized by high Na 2 O/K 2 O, Sr/Y, and (La/Yb) n ratios as well as high Sr concentrations, low Mg # [molar 100 × Mg/(Mg + Fe 2 + tot )] values, and low heavy rare earth element and Y concentrations, all of which indicate an LMAR affinity. The samples have relatively high initial 87 Sr/ 86 Sr ratios (0.7054–0.7095), and low ε Nd (t) (− 11.90 to − 22.20) and ε Hf (t) (− 16.7 to − 32.7) values, indicative of a lower continental crust origin. The presence of Neoproterozoic (754–542 Ma) and inherited Late Triassic (220 Ma) metamorphic zircons within the late Early Cretaceous LMAR and the relatively high 206 Pb/ 204 Pb ratios of these rocks suggest that they formed from primary magmas derived from partial melting of Yangtze Craton (YC) basement material that had undergone ultrahigh-pressure metamorphism. In contrast, the presence of Paleoproterozoic and Archean inherited zircons within early Early Cretaceous LMAR in this area and the relatively low 206 Pb/ 204 Pb ratios of these rocks are indicative of derivation from primary magmas generated by partial melting of the thickened lower continental crust of the North China Craton (NCC). These rocks may have formed in an extensional environment associated with the upwelling of asthenospheric mantle material. The presence of YC basement material within the NCC in the Sanmenxia–Houma area suggests that the deeply subducted Yangtze slab influenced an area of ~ 100 km in lateral extent within the southern margin of the central NCC during the Triassic. [ABSTRACT FROM AUTHOR]

[Display omitted] • 140–120 Ma volcanic magmatism is recorded in the SNCC. • Yangtze Craton material occurs beneath the SNCC. • Intense crust-mantle interaction is recorded in the SNCC. This study presents new geochronological and geochemical data for Early Cretaceous volcanic rocks in the southern margin of the North China Craton (NCC), to discuss the crust–mantle interaction. The studied rocks include pyroxene andesites from Daying Formation, hornblende andesites and andesites from Jiudian Formation, and rhyolites from a hitherto unnamed Formation. These rocks formed in Early Cretaceous (138–120 Ma), with enrichment in light rare earth elements (REE), depletion in heavy REE and arc-like trace elements characteristics. Pyroxene andesites show low SiO 2 contents and enriched Sr–Nd–Pb–Hf isotopic compositions, with orthopyroxene phenocryst and Paleoproterozoic (2320–1829 Ma) inherited zircons, suggesting that they originated from lithospheric mantle after metasomatism with NCC lower crustal materials. Hornblende andesites have low SiO 2 contents and high Mg# (Mg# = 100 Mg/(Mg + Fe2+)) values, indicating a lithospheric-mantle origin. Considering the distinct whole-rock Sr isotopic compositions we divide them into two groups. Among them, the low (87Sr/86Sr) i andesites possess amount inherited Neoarchean to Neoproterozoic (2548–845 Ma) zircons, indicating the origin of lithospheric mantle with addition of Yangtze Craton (YC) and NCC materials. In comparison, the high (87Sr/86Sr) i andesites, with abundant Neoarchean–Paleozoic inherited zircons (3499–261 Ma), are formed by partial melting of lithospheric mantle with incorporation of NCC supracrustal rocks and YC materials. Rhyolites have extremely high SiO 2 (77.63–82.52 wt.%) and low total Fe 2 O 3 , Cr, Ni contents and Mg# values, combined with ancient inherited zircon ages (2316 and 2251 Ma), suggesting an origin of NCC lower continental crust. Considering the presence of resorption texture of quartz phenocryst, we propose a petrogenetic model of 'crystal mushes' for rhyolites prior to their eruption. These constraints record the intense crust–mantle interaction in the southern margin of the NCC. Given the regional data and spatial distribution of Early Cretaceous rocks within NCC, we believe that the formation of these rocks is related to the contemporaneous far-field effect of the Paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

Abstract: The destruction (or reactivation) of the North China Craton (NCC) is one of the important issues related to the Phanerozoic evolution of eastern China, although the processes of destruction remain debated. Two main mechanisms – delamination and thermal/chemical erosion – have been proposed based on the geochemistry of Mesozoic–Cenozoic basalts and entrained deep–seated xenoliths. A key criterion in distinguishing between these mechanisms is the nature of the melt, derived from delaminated crust or the asthenosphere, that modified the lithospheric mantle. Here we investigate the mechanism of destruction of the NCC based on mineral compositions and oxygen isotopic data from olivines, and strontium isotopic data for clinopyroxenes within websterite xenoliths from the Early Cretaceous Feixian basalts in the eastern NCC. Olivines in websterite xenoliths have higher Mg# (86–86.4), Ni content (2187–2468ppm), and lower Ca (983–1134ppm), Ti (58.1–76.1ppm), and Mn (1478–1639ppm) contents than olivine phenocrysts (Mg#=71.0–77.3, Ni=233–1038ppm, Ca=1286–2857ppm, Ti=120–300ppm, and Mn=2092–4106ppm) from Late Cretaceous basalts. Additionally, olivines in websterite xenolith have δ18O values of 7.10±0.21‰ to 8.40±0.21‰, evidently higher than those of typical mantle-derived olivines. Similarly, orthopyroxenes (Opx) and clinopyroxenes (Cpx) in the websterite xenoliths have much higher Mg# (86.3–89.2 and 87.5–90.3, respectively), and Ni contents (1097–1491ppm and 581–809ppm, respectively) than orthopyroxene- and clinopyroxene-phenocrysts (Opx: Mg#=82.2–83.9, Ni=730–798ppm; Cpx: Mg#=74.2–84.6, Ni=117–277ppm) from Late Cretaceous basalts. The 87Sr/86Sr ratios of clinopyroxenes in the websterite xenoliths range from 0.70862 to 0.70979, and are much higher than those of clinopyroxene grains from peridotite xenoliths and basalts. These data indicate that olivines are the residue of ancient lithospheric mantle that was modified intensively by a melt derived from recycled continental crust, and that the silicic and calcic metasomatic melt might have been derived from the partial melting of the subducted Yangtze slab and delaminated lower crust of the NCC. The existence of recycled continental crust in the Mesozoic lithospheric mantle implies that delamination was an important mechanism of destruction of the NCC. [Copyright &y& Elsevier]