42 research outputs found
Geochronology and geochemistry of late Archean adakitic plutons from the Taishan granite-greenstone Terrain: Implications for tectonic evolution of the eastern North China Craton
No full textGeochronology and geochemistry of late Archean adakitic plutons from the Taishan granite-greenstone Terrain: Implications for tectonic evolution of the eastern North China Craton
No full textGeochronology and geochemistry of the late Paleoproterozoic aluminous A-type granite in the Xiaoqinling area along the southern margin of the North China Craton: Petrogenesis and tectonic implications
No full textGeochronological and geochemical constraints on the coexistent N-MORB- and SSZ-type ophiolites in Babu area (SW China) and tectonic implications
No full textAge and geochemistry of the early Mesoproterozoic A-type granites in the southern margin of the North China Craton: Constraints on their petrogenesis and tectonic implications
No full textNeoarchean siliceous high-Mg basalt (SHMB) from the Taishan granite-greenstone terrane, Eastern North China Craton: Petrogenesis and tectonic implications
No full textZircon geochronology and Hf isotopes of Mesozoic intrusive rocks from the Yidun terrane, Eastern Tibetan Plateau: Petrogenesis and their bearings with Cu mineralization
No full textPetrogenesis of the Late Paleoproterozoic (similar to 1.84Ga) Yuantou A-type granite in the southern margin of the North China Craton and its tectonic implications
No full textThe North China Craton (NCC) has been successively recognized many Late Paleoproterozoic to Early Mesoproterozoic A type granites, showing unique geochemistry characteristics and particular formation environment, which would provide further important insights into their petrogenesis and tectonic transition from the formation of crystalline basement to the deposition of stable sedimentary cover in NCC. Here we report systematic investigation on petrology, geochronology, elemental geochemistry, and Nd-Hf-O isotopic characteristics of the Yuantou pluton in the southern margin of the NCC. The results show that the Yuantou pluton mainly consists of syenogranite, which was emplaced at 1841 +/- 4 Ma. All rocks are rich in ferroan (FeOT/(FeOT + MgO) = 0.75 similar to 0.86) and alkaline (K2O + Na2O = 8.11%-9.13%, K2O/Na2O > 1), but poor in MgO (0.28%similar to 0.56%), P2O5 (0.04%similar to 0.08%) and MnO (0.03%similar to 0.04%). Additionally, they show enrichment of LILEs (Rb, Th, U, K), depletion of HFSEs (Nb, Ta, Zr, Hf) with negative Eu and Sr anomalies. Their high 10,000Ga/Al ratios (>2.76) with metaluminous to peraluminous characteristics, containing biotite without alkali mafic minerals, show an affinity to aluminous A-type granite. The Late Paleoproterozoic A-type granite displays low whole-rock epsilon(Nd) (t) value (-4.68) with two-stage Nd model age of 2.70Ga, low zircon e(Hf) ( t) values (-12.0 similar to 4.71) with zircon two-stage Hf model ages of 3.22 similar to 2.78Ga, and high zircon 8180 values (5.4 parts per thousand to 6.5 parts per thousand, weighted mean =6.1 parts per thousand), indicating that the Yuantou A-type granite was derived predominantly from partial melting of the ancient continental crust. Combined with above results and regional geological data, the Yuantou A-type granite was related to the underplating of mafic magmas in a post-collisional regime, marking the end of similar to 1.85Ga orogenic movement in the NCC
