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    Yongqing Chen

    The giant Gejiu Sn–Cu polymetallic ore deposit is one of the largest Sn producers in the world, and is related in time and space to highly evolved S type granitic intrusion. The mineralization processes can be divided into four stages:... more
    The giant Gejiu Sn–Cu polymetallic ore deposit is one of the largest Sn producers in the world, and is related in time and space to highly evolved S type granitic intrusion. The mineralization processes can be divided into four stages: (I) skarnization; (II) greisenization; (III) cassiterite–sulfid; and (IV) cassiterite–tourmaline–quartz. Five types of fluid inclusions were recognized using optical petrography, microthermometry, and Raman spectroscopy. The results of microthermometry revealed the evolution of the ore-forming fluid, from a high temperature with low–to–high salinity to a low temperature with low–to–intermediate salinity. Stage I, skarn Sn–Cu ores were formed by bimetasomatism between the granitic intrusion and the surrounding rock under near–critical conditions with the help of ore-forming fluid. Stage II, the fluid was separated into the coexisting liquid and vapor phases in equilibrium condition, and a large amount of cassiterite–scheelite–beryl–lithium muscovite mi...
    The Gejiu Anisian alkaline basalts (GAAB), distributed in the southern part of the Emeishan large igneous province (ELIP), are crucial to understand the tectonomagmatic activity during the Triassic. Geochronological, geochemical, and... more
    The Gejiu Anisian alkaline basalts (GAAB), distributed in the southern part of the Emeishan large igneous province (ELIP), are crucial to understand the tectonomagmatic activity during the Triassic. Geochronological, geochemical, and Sr-Nd-Pb isotopic analyses were systematically applied to explore the origin, petrogenesis, and tectonic setting of the GAAB, and how they relate to the ELIP. Zircon U-Pb dating set the eruption date at 244 Ma. Most of the samples belonged to alkaline basalts and had high TiO2 (2.14–3.23 wt.%) and MgO (4.43–19.58 wt.%) contents. Large ion lithophile elements (LILEs) were enriched relative to high field strength elements (HFSEs). The rare earth elements (REEs) and trace element signatures in the normalized diagrams were similar to oceanic island basalts (OIB) and Emeishan high-Ti basalts. These samples had consistent Sr-Nd isotope compositions: the initial 87Sr/86Sr values ranged from 0.7044 to 0.7048 and εNd(t) = 3.25–4.92. The Pb isotopes were more com...
    The Guilaizhuang gold deposit, with an average grade of 8.10 g/t Au and reserves of over 30 mt, is a subvolcanic epithermal deposit. The deposit is hosted in Paleozoic carbonate rocks in the western Shandong metallogenic terrane of the... more
    The Guilaizhuang gold deposit, with an average grade of 8.10 g/t Au and reserves of over 30 mt, is a subvolcanic epithermal deposit. The deposit is hosted in Paleozoic carbonate rocks in the western Shandong metallogenic terrane of the littorine Pacific metallogenic domain, ...
    Jinla Pb-Zn-Ag poly-metallic ore field across China and Myanma, is tectonically located in the south segment of the Mengtong–Gengma–Ximeng passive continental margin of Proterozoic era-Palaeozoic era, and the eastern margin of the... more
    Jinla Pb-Zn-Ag poly-metallic ore field across China and Myanma, is tectonically located in the south segment of the Mengtong–Gengma–Ximeng passive continental margin of Proterozoic era-Palaeozoic era, and the eastern margin of the Baoshan–Shantai Massif. Mineralization related granitoids within the ore field include Laochang amphibole admellite, Menglinshan biotite admellite and Nanla K-feldspar granite-porphyry. This paper systematically presents the characteristics of the