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Adakitic rocks are often considered as a key to deciphering the genesis of Archean TTGs and the early crustal growth. Granites from the Huichizi pluton in the North Qinling (NQ) unit have high Sr/Y and (La/Yb)N ratios similar to adakites. Their relatively high SiO2, K2O, and Na2O and very low MgO, Cr, and Ni contents are in the range of high-SiO2 adakites and early Archean TTGs and are compositionally...
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy. The article duplicates significant parts of a paper that had already appeared in, and was withdrawn from Precambrain Research (http://dx.doi.org/10.1016/j.precamres.2014.08.012). The paper was also submitted without the knowledge of all the co-authors, and included another,...
Titanite U–Pb isotopic and major and trace element compositions of one mafic garnet granulite from a rare suite of lower crustal xenoliths (e.g., eclogite, garnet pyroxenite, and mafic garnet granulite) hosted in Early Cretaceous dioritic porphyries in the Xu–Huai area along the southeastern margin of the North China Craton (NCC) were analyzed by laser ablation ICP-MS. Titanite occurs as granular...
S-type peraluminous granite can crop out in various tectonic settings. The Paleozoic Piaochi granitic intrusion is a large S-type peraluminous intrusion located in the North Qinling orogen, and has important implication for its tectonic evolution. Though intensively studied, the age and tectonic setting of this intrusion are still controversial. In this study, we carried out an integrated study of...
Accretionary orogenic belts are considered the most important sites for the generation of continental crust. However, it is still not very clear whether in such settings the continental crust has been significantly transported back to the mantle accompanied with its lateral growth. Continental UHP rocks, the best indicators of the recycling of the continental crust, have rarely been discovered in...
The tectonic properties of the Erlangping unit and the subduction polarity of oceanic basins in the North Qinling–Tongbai orogen have been the focus of debate for more than twenty years. The resolution of these controversies hinges on the refined constraints on the location and nature of subduction-related magmatism. In this contribution, we provide a combined study of zircon U–Pb ages, major and...
A rare large clinopyroxene megacryst (referred to as type 1) collected from the Hannuoba basalt, North China was studied. It is distinguished from the prevalent clinopyroxene megacrysts (type 2) by garnet and orthopyroxene exsolutions and by elemental and Sr–Nd isotopic compositions. The type 1 clinopyroxene megacryst has higher Cr and Nb contents and Mg# (82.9) than the type 2 clinopyroxene megacrysts...
Mafic dolerite dykes form a series of swarms that are widespread across the North China Craton (NCC). We present U–Pb zircon ages, geochemical data, and Sr–Nd–Hf isotopic data for representative samples of the Shaanxi dolerite dykes in the southern NCC. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb zircon analyses for three samples yield ages ranging from 448.1±1.2 to...
Precambrian mafic dykes in the North China Craton (NCC) consist of dolerite. Geochronological, geochemical, and whole-rock Sr–Nd isotopic analyses were performed on this suite of mafic dykes to characterise their ages and petrogenesis. Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) U–Pb zircon analyses yield consistent ages ranging from 837.9±4.8Ma to 2510±18Ma for seven of...
LA-(MC)-ICPMS trace element, U–Pb and Hf isotope analyses were performed on zircons from continental-derived retrograde high-pressure metamorphic rocks, which were attested by the occurrence of HP mineral inclusions in metamorphic zircons, from the Huwan shear zone in the western Dabie orogen. Zircons in a schist sample are mostly detrital and gave U–Pb ages from 1212 to 2312Ma, suggesting that the...
It is intriguing whether the formation of granulite in an orogenic belt is related to magmatism and crustal growth. The Tongbai orogen is one of the particular areas in the Qinling–Tongbai–Dabie–Sulu orogen that contains both granulites and associated arc magmatic rocks, and thus is an optimal place to address this issue. However, the formation age and genesis of the granulites and their relations...
Hydrothermally altered rocks are products of fluid–rock interactions, and typically preserve numerous quartz veins that formed as chemical precipitates from fluids that fill up cracks. Thus, quartz veins are the record of the fluid system that involved fracture flow in the direction of changing temperature or pressure. In order to decipher the fluid activity in the Sulu ultrahigh-pressure (UHP) terrane...
Rutile and zircon in eclogites from the main hole of the Chinese Continental Scientific Drilling (CCSD-MH) were analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and electron microprobe (EMP). Both single spot and profile analyses of large matrix rutiles (>60μm) generally demonstrate core–rim variability of Pb, Sr, Zr and U. Pb and Sr show enrichment at the rims,...
Post-orogenic granitic and associated mafic rocks from northeastern (NE) China consist of granodiorite and gabbro intrusions. We report here upon new U–Pb zircon ages, geochemical data and Sr–Nd–Hf isotopic data for these rocks. LA-ICP-MS U–Pb zircon analysis yields an age of 262.8±1.0Ma for the granitic rocks, and a uniform age of 262.1±0.7Ma for the gabbro. Most of the granitic and mafic rocks are...
Geochronological, geochemical and whole-rock Sr–Nd isotopic analyses have been completed on a suite of alkaline ultramafic dykes from southwest (SW) Guizhou Province, China with the aim of characterising their petrogenesis. The Baiceng ultramafic dykes have a LA-ICP-MS zircon 206 Pb/ 238 U age of 88.1±1.1Ma (n=8), whereas two phlogopites studied by 40 Ar/ 39 Ar dating...
Late Mesozoic (122.5–127 Ma) mafic dykes (dolerite-porphyries) in the Beibo gold district, Shandong Province, eastern North China Craton, can be subdivided into two groups (high-K and low-K) based upon K 2 O content. They are characterised by enrichment in light rare earth element (LREE) and some large ion lithophile elements (LILEs) (e.g., Rb, Ba and Sr), similar concentrations of heavy rare...
Detailed geochemical (major and trace elements, Sr-Nd isotope) and new zircon U-Pb dating data for eclogite and garnet-clinopyroxenite xenoliths within the Mesozoic adakitic rocks from the Xuzhou-Suzhou area in central China provide insight into origin of their protolith and the Mesozoic tectonic evolution of the eastern North China Craton (NCC). The eclogite xenoliths have a basaltic bulk composition...
Post-orogenic alkaline intrusions and associated mafic dikes from the Sulu orogenic belt of eastern China consist of quartz monzonites, A-type granites and associated mafic dikes. We report here U–Pb zircon ages, geochemical data and Sr–Nd–Pb–Hf isotopic data for these rocks. The SHRIMP U–Pb zircon analyses yield consistent ages ranging from 120.3±2.1 Ma to 126.9±1.9 Ma for five samples from the felsic...
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