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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]

Apatite is widely utilized to reflect the character and petrogenesis of the parental felsic magma. The compositional variation of apatite from mafic rocks and its applicability to the record of whole-rock are still not well understood. In this study, we present the in situ geochemical analysis of apatite from two types of mafic rocks in the northeastern North China Craton (amphibole-rich mafic rocks for group 1, and pyroxene-rich mafic rocks for group 2). All apatite samples display typically right-sloping rare earth element (REE) patterns, with enrichment in light REE relative to heavy REE, and homogeneous Nd isotopic compositions, suggesting a magmatic origin. Higher apatite REE contents in mafic rocks of group 2 than those of group 1 show a different crystallization sequence in apatite. Extensive apatite crystallization in amphibole-rich mafic rocks, occurs earlier than in pyroxene-rich mafic rocks. The magma differentiation is responsible for the low apatite REE concentrations in group 1 mafic rocks. Combined with previous apatite data, both apatite REE patterns and compositional variations in mafic rocks are mainly controlled by the composition of the original melt. The crystallization of titanite before apatite impoverishes melts in the apatite-compatible trace elements (e.g., middle REE), whereas the crystallization of plagioclase concurrently with apatite can cause some subtle compositional variations of Sr and light REE. Apatite in mafic rocks exhibits higher Sr concentrations than in felsic rocks, which is most likely attributed to the weakening extent of the plagioclase crystallization. [Display omitted] • Apatite compositions in mafic rocks mainly depend on the parental melt. • Apatite grains from appinite crystallize earlier than those from gabbro. • The crystallization of mineral phases can cause apatite compositional variations. [ABSTRACT FROM AUTHOR]

• 1813–1789 Ma A-type granites were identified in southern NCC. • A-type granites originated from partial melting of TTG of Taihua Complex. • The A-type magmatism was in respond to the breakup of Columbia supercontinent in post-collisional setting. A-type granites are produced commonly in extensional settings and they are important proxies to track breakup of continent. Here we report systematic studies on geochronology and geochemical features of A-type granites in Songxian–Ruyang region, southern margin of the North China Craton (NCC), in order to constrain their petrogenesis and tectonic implications. Zircons from these granites show oscillatory zoning and high Th/U ratios (0.12 to 1.26), indicating a magmatic origin. LA–ICP–MS zircon U–Pb dating shows that they were emplaced at 1813 to 1789 Ma, indicating that they were formed in late Paleoproterozoic. Geochemically, these rocks are high in SiO 2 (67.51–74.42 wt%) and total alkalis (Na 2 O + K 2 O = 7.76–10.19 wt%), and low in MgO (0.09–1.31 wt%), CaO (0.09–1.11 wt%) and P 2 O 5 (0.12–0.26 wt%) contents, with negative Nb, Ta, Sr, P and Ti anomalies. They are characterized by high FeOT/(MgO + FeOT), 10000 Ga/Al ratios (1.57–3.15) and Zr + Nb + Ce + Y contents (566–835 ppm). They are also characterized by high calculated Zr saturation temperatures (892–918 °C), high Ti-in-zircon temperatures (693–912 °C) and metaluminous to weakly peraluminous natures, which are typical features of aluminous A-type granites, further belonging to the A 2 granites. The low zircon ε Hf (t) values (–13.8 to –8.6), along with the low whole rock ε Nd (t) values (–8.62 to –6.10) and low apatite ε Nd (t) values (–8.31 to –6.56), indicate that the Songxian–Ruyang A-type granites were derived from partial melting of the calc-alkaline tonalitic–trondhjemitic–granodioritic gneisses in Taihua Complex, and they were formed in post-collisional extensional setting. Combined with coeval regional granitoids, the south margin of the NCC is in a continuous extensional setting during 1.8–1.6 Ga, and the Songxian–Ruyang A-type granites can represent a response of the breakup of Columbia supercontinent. [ABSTRACT FROM AUTHOR]

• 1.85–1.80 Ga plagiogranites were identified in the JLJB. • The late Paleoproterozoic plagiogranites were formed by partial melting of high-T hydrated oceanic crust. • The JLJB was an arc–continent collision belt during the Paleoproterozoic. Paleoproterozoic plagiogranites were identified in the Gaoliduntai area of the Jiao–Liao–Ji Belt (JLJB), North China Craton (NCC). We conducted a geochronological, geochemical, isotopic, and mineral chemical investigation of the plagiogranites to constrain their petrogenesis and tectonic implications. The Gaoliduntai plagiogranites yielded zircon U–Pb ages of 1802 ± 10, 1828 ± 18, and 1853 ± 11 Ma, indicating emplacement at the late Paleoproterozoic. Geochemically, They are characterized by high SiO 2 and Na 2 O, and low K 2 O and TiO 2 contents, with low total rare earth element (REE) concentrations. They also exhibit enrichment in light REEs and large-ion lithophile elements (e.g., Cs, Rb and Sr), and depletion in heavy REEs and high-field-strength elements (e.g., Nb and Ta). The plagiogranites show varying initial 87Sr/86Sr ratios (0.7012–0.7053), whole-rock ε Nd (t) values (–8.23–+1.15) and apatite ε Nd (t) values (–4.78–+3.30), with whole-rock 206Pb/204Pb (t) (14.223–16.733), 207Pb/204Pb (t) (15.310–15.644) and 208Pb/204Pb (t) (35.310–35.998) values, indicating a depleted mantle source modified with an enrichment component. Zircons in the plagiogranites have positive ε Hf (t) values (+1.0 to +6.4) and T DM2 (Hf) ages of 2408–2078 Ma. Zircons δ18O compositions (2.1‰ to 4.5‰) are lower than the zircons from normal mantle but show similar features to typical plagiogranites. Furthermore, the plagioclases in these plagiogranites are albite (Ab = 95–99). These features lead us to propose that the Gaoliduntai plagiogranites formed by partial melting of high-temperature mafic oceanic crust, with contributions from delaminated crustal components. We suggest that the Paleoproterozoic Gaoliduntai plagiogranites provide evidence of the involvement of ancient oceanic crust in the tectonic evolution of the JLJB. Based on regional geological features and previous studies, we propose that the JLJB was an arc–continent collision belt during the Paleoproterozoic, and that the Gaoliduntai plagiogranites formed in an extensional tectonic setting. [ABSTRACT FROM AUTHOR]

Abstract: We performed zircon U–Pb dating and analyses of major and trace elements, and Sr–Nd–Pb isotopes for granitoids in the Bengbu area, central China, with the aim of constraining the magma sources and tectonic evolution of the eastern North China Craton (NCC). The analyzed zircons show typical fine-scale oscillatory zoning, indicating a magmatic origin. Zircon U–Pb dating reveals granitoids of two ages: Late Jurassic and Early Cretaceous (206Pb/238U ages of 160Ma and 130–110Ma, respectively). The Late Jurassic rocks (Jingshan intrusion) consist of biotite-syenogranite, whereas the Early Cretaceous rocks (Huaiguang, Xilushan, Nushan, and Caoshan intrusions) are granodiorite, syenogranite, and monzogranite. The Late Jurassic biotite-syenogranites and Early Cretaceous granitoids have the following common geochemical characteristics: SiO2 =70.35–74.56wt.%, K2O/Na2O=0.66–1.27 (mainly<1.0), and A/CNK=0.96–1.06, similar to I-type granite. The examined rocks are characterized by enrichment in light rare earth elements, large ion lithophile elements, and U; depletion in heavy rare earth elements, Nb, and Ta; and high initial 87Sr/86Sr ratios (0.7081–0.7110) and low ε Nd (t) values (−14.40 to −22.77), indicating a crustal origin. The occurrence of Neoproterozoic magmatic zircons (850Ma) and inherited early Mesozoic (208–228Ma) metamorphic zircons within the Late Jurassic biotite-syenogranites, together with the occurrence of Neoproterozoic magmatic zircons (657 and 759Ma) and inherited early Mesozoic (206–231Ma) metamorphic zircons within the Early Cretaceous Nushan and Xilushan granitoids, suggests that the primary magmas were derived from partial melting of the Yangtze Craton (YC) basement. In contrast, the occurrence of Paleoproterozoic and Paleoarchean inherited zircons within the Huaiguang granitoids indicates that their primary magmas mainly originated from partial melting of the NCC basement. The occurrence of YC basement within the lower continental crust of the eastern NCC indicates that the YC was subducted to the northwest beneath the NCC, along the Tan-Lu fault zone, during the early Mesozoic. [Copyright &y& Elsevier]

This paper reports new whole-rock major and trace element, Sr Nd isotopic, and zircon U Pb and Hf O isotopic data for Late Triassic intrusive rocks on Liaodong Peninsula, NE China, aiming to constrain the petrogenesis of these rocks in terms of lithospheric thinning in the northeastern North China Craton (NCC). New zircon U Pb data indicate that the rocks were emplaced during the Late Triassic (220–211 Ma). Based on petrology, petrography and geochemistry, we divided these rocks into three groups. The Group 1 rocks, including hornblende gabbro, hornblende diorite and mafic vein, show low SiO 2 , Na 2 O + K 2 O and high MgO contents, with (87Sr/86Sr) i (0.7066–0.7071), ε Nd (t) (−10.6 to −5.7), ε Hf (t) (−16.6 to +1.5), and δ18O (7.06‰–7.82‰) values, indicating that they were formed by partial melting of lithospheric mantle with addition of lower continent crust materials. The Group 2 rocks, including syenites, display high SiO 2 , Na 2 O + K 2 O and low MgO contents, with (87Sr/86Sr) i (0.7064–0.7073), ε Nd (t) (−14.8 to −14.5), ε Hf (t) (−11.7 to −5.7), and δ18O (5.49‰–6.37‰) values, indicating they were originated through partial melting of lithospheric mantle with continent crust materials added, coupled by fractional crystallization of mafic minerals. The Group 3 rocks, including monzogranite and syenogranite, show high SiO 2, Na 2 O + K 2 O and low MgO contents, with different isotopic signatures: the former shows (87Sr/86Sr) i (0.7085–0.7087), ε Nd (t) (−17.0 to −16.8), ε Hf (t) (−17.9 to −4.4) and δ18O (6.10‰–6.95‰) values. The latter shows higher ε Nd (t) (−9.0 to −8.1), ε Hf (t) (−3.4 to +1.2) and lower δ18O (5.52‰–7.29‰) values. Combined with the adakitic features of monzogranite and different two model ages, we believe they were derived from partial melting of ancient thickened lower crust and juvenile crust, respectively. Together with the spatial and temporal distribution of the Late Triassic rocks, we believe that these rocks were related to the collision between NCC and Yangtze Craton, and the initiation of lithospheric thinning of NCC in eastern segment began in Late Triassic. Unlabelled Image • Late Triassic intrusive rocks on Liaodong Peninsula were formed between 220 and 211 Ma. • These rocks were formed after the collision between NCC and YC. • Lithospheric thinning of northeastern NCC began at ~220 Ma. [ABSTRACT FROM AUTHOR]

Abstract: We present geochronological, geochemical, and Sr–Nd–Pb isotope data for late Mesozoic granitoids in southern Jilin province, northeastern China, with the aim of ascertaining the genesis of the granitoids, and further constraining the nature of the lower crust and Mesozoic tectonic evolution of the eastern North China Craton (NCC). The results of LA-ICP-MS zircon U–Pb dating for seven granitoid plutons (from northeast to southwest, the Liudaogou, Toudaogou, Xingfu, Ji''an, Yushulinzi, Lujiangchun, and Zhenjiang plutons) indicate that they formed in the Early Cretaceous (130–122Ma). The granitoids consist of granodiorite, monzogranite, syenogranite, and alkali feldspar granite. Geochemically, they have SiO2 =61.8–76.2%, MgO=0.04–3.27%, Mg# [100(Mg/(Mg+Fe2+)]=7–55, and Al2O3 =12.7–16.2%, and they are characterized by enrichment in light rare earth elements (LREEs) and large ion lithophile elements (LILEs, such as Rb, Cs, and K), and depletion in heavy rare earth elements (HREEs) and high field strength elements (HFSEs, such as Nb and Ta). Their initial 87Sr/86Sr ratios, ε Nd(t) values, and initial 206Pb/204Pb ratios range from 0.70627 to 0.71067 (except for one sample), −1.9 to −13.9, and 17.84 to 18.47, respectively. Compared with the Zhenjiang, Yushulinzi, Lujiangchun, and Ji''an plutons from the southwestern part of the study area [ε Nd(t)=−9.8 to −13.9 and TDM2 =1726–2058Ma], those from the northeastern part of the study area (the Xingfu, Toudaogou, and Liudaogou plutons) have relatively high ε Nd(t) values (−1.9 to −8.8), low TDM2 (1081–1641Ma). The Early Cretaceous granitoids with high SiO2 contents and low Mg# from the southwestern part of the study area, together with those with high SiO2 contents and low Mg# from the northeastern part of the study area, were possibly mainly derived from the partial melting of Paleoproterozoic lower crust, with a minor contribution from younger material. The latter granitoids, together with the Zhenjiang granodiorites from the southwestern part of the study area, may have formed via mixing between crust- and mantle-derived melts. The rock associations and geochemistry of the southern Jilin granitoids, together with the contemporaneous volcanic rocks in this area, indicate that they formed in an active continental margin setting associated with the oblique subduction of the Paleo-Pacific Plate beneath the Eurasian continent in the Early Cretaceous. [Copyright &y& Elsevier]

Abstract: In this paper, we report on zircon U–Pb dating, Hf isotopes, major and trace elements, and Sr–Nd isotope data, with the aim of constraining the petrogenesis and regional tectonic evolution of late Paleozoic volcanic rocks in the Zhangguangcai Range of eastern Heilongjiang Province, NE China. Located in the eastern segment of the Central Asian Orogenic Belt (CAOB), between the Siberian and North China cratons, the late Paleozoic volcanic rocks in the Zhangguangcai Range are composed mainly of basalt, basaltic andesite, rhyolite, and minor dacite. The results of LA–ICP–MS zircon U–Pb dating for two basaltic rocks, three rhyolites, and one dacite indicate that they formed in the early Permian (ca. 292Ma). The mafic rocks have SiO2 =50.13–53.80wt.%, K2O=0.98–2.28wt.%, Mg#=0.51–0.71, Cr=144–541ppm, Ni=74–260ppm, (87Sr/86Sr)i =0.7044, and ε Nd (t)=+4.28, whereas the felsic rocks have SiO2 =69.12–77.98wt.%, K2O=3.09–5.33wt.%, Mg#=0.17–0.36, (87Sr/86Sr)i =0.7032, and ε Nd (t)=+4.32. These data are typical of bimodal volcanism. The mafic volcanic rocks are characterized by a strong enrichment in large ion lithophile elements (LILEs) such as Rb, Ba, Sr, and Pb, depletion in high field-strength elements (HFSEs) such as Nb, Ta, and Ti, depletion in heavy rare-earth elements (HREEs), and weak negative Eu anomalies (Eu/Eu* =0.88–0.94). On the other hand, the felsic rocks show a strong depletion in Nb, Ta, Sr, P, and Ti, enrichment in Th, U, and K, and relatively large negative Eu anomalies (Eu/Eu* =0.28–0.95). Taken together, these data suggest that the mafic magma was derived from the partial melting of a depleted lithospheric mantle, modified by subducted slab-derived fluids, and that the felsic magma originated by partial melting of newly accreted crust. The early Permian bimodal volcanic rocks, together with the coeval A-type granites, indicate an extensional environment, similar to a back-arc basin. Such a setting was possibly related to subduction of the Paleo-Asian oceanic plate beneath the Jiamusi and Songnen–Zhangguangcai Range massifs. [Copyright &y& Elsevier]

We report geochemical data of apatites from Mesozoic granitoids in the northeastern North China Craton (NCC), and discuss the relationship between apatite and whole-rock compositions with the aim of using apatite geochemical data to constrain granitoid petrogenesis. Measured Sr contents and Sr/Y ratios of apatites exhibit positive correlations with those of their host rocks, and ε Nd (t) values of apatites display a strong linear relationship with ε Hf (t) values of zircons in the granitoids. In addition, apatites exhibit similar rare-earth element (REE) distribution patterns with their host rocks, although apatites have much higher REE contents. Sr/Y–Y variation diagram for apatite is proposed to distinguish adakitic rock from non-adakitic. The REE patterns of apatites, together with other geochemical indexes, can also be used to discriminate highly fractionated granitoids from unfractionated I-type granite or other type granite. The geochemical and Nd isotopic compositions of apatites have well revealed the magma source of Mesozoic granitoids in the northeastern NCC. In conclusion, we highlight that apatite geochemistry reflects the whole-rock geochemical characteristics of granitoids and has the potential to track granite detritus. • Geochemical data of apatites from the Mesozoic granitoids in the NCC are reported. • Apatite REE patterns are governed by multiple factors. • Sr, Y contents and Sr/Y ratios in apatites can be used to identify adakitic rocks. • Apatite REE patterns can be used to identify highly fractionated I-type granitoids. [ABSTRACT FROM AUTHOR]