Geochemical and Geochronological Constraints on a Granitoid Containing the Largest Indosinian Tungsten (W) Deposit in South China (SC): Petrogenesis and Implications

Chuankou tungsten (W) ore field, with an estimated WO3 reserve exceeding 300,000 tonnes, is so far the largest Indosinian (Triassic) granite-related W ore field in South China. However, the precise emplacement ages, sources of granitoids, and their relationship with W mineralization are still not well understood. In this research, four main magmatic stages (G-1 to G-4) have been identified in the Chuankou ore field, including G-1 (phase I, biotite monzogranite), G-2 (phase II, two-mica monzogranite), G-3 (phase III, fine-grained granite), and G-4 (phase IV, granite porphyry). LA-ICP-MS U-Pb dating of zircon grains from granitoids of the Chuankou W ore field yields emplacement ages of 230.8 ± 1.6 Ma, 222.1 ± 0.56 Ma, 203.1 ± 1.6 Ma, and 135.5 ± 2.4 Ma, respectively. Granitoids from the Chuankou ore field contain a large amount of peraluminous minerals such as biotite, musvite, garnet and tourmaline. Geochemically, the granitoids have high Si and Al (A/CNK > 1.1) content but low alkali, Fe, Mg, Mn, and Ca content. Moreover, there is enrichment of Rb, Zr, Hf, Th, and U, but depletions of Ba, Sr, P, and Ti. The granitoids have especially low Zr + Nb + Ce + Y and high Rb/Ba ratios, further indicating a highly fractionated S-type granite affinity with a significant crystal fractionation process in regard to K-feldspar, plagioclase, biotite, Ti-bearing minerals (except rutile), zircon, apatite, allanite, and monazite. Whole-rock εNd(t) and TDM2 values are −10.77 and 2090 Ma for G-1, −9.09 to −7.47 and 1764–1684 Ma for G-2, −10.07 to −6.53 and 1669–1471 Ma for G-3, respectively, indicating that the Chuankou granitoids were derived from two episodes of partial melting of the Paleoproterozoic to Mesoproterozoic metamorphic basement. Trace elements within the zircons and whole-rock geochemistry yielded evidence of the close relationship between W mineralization and G-1 and G-2 granitoids of the Chuankou ore field. The batholith of the Chuankou ore field was formed 20–10 Ma later than the peak age of the collisions orogeny and formed in a post-collisional setting.

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In situ LA ICP-MS analysis of trace elements in scheelite from the Xuefeng Uplift Belt, South China and its metallogenic implications

Ore Geology Reviews ◽

10.1016/j.oregeorev.2021.104097 ◽

2021 ◽

Vol 133 ◽

pp. 104097

Author(s):

Dexian Zhang ◽

Junqing Pan ◽

Jianfeng Gao ◽

Tagen Dai ◽

Richard C. Bayless

Keyword(s):

Trace Elements ◽

South China ◽

Ms Analysis ◽

Icp Ms

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The discovery adakitic rock along the Phan Si Pan zone in northwestern Vietnam and Cu-Au-Mo mineralization

Science and Technology Development Journal ◽

10.32508/stdj.v16i1.1427 ◽

2013 ◽

Vol 16 (2) ◽

pp. 5-15

Author(s):

Hieu Trung Pham

Keyword(s):

Theoretical Basis ◽

Porphyry Copper ◽

Mineral Resources ◽

Epithermal Deposit ◽

Porphyry Copper Deposits ◽

Rock Types ◽

Icp Ms ◽

Close Relationship ◽

Plasma Mass Spectrometry ◽

Type Granite

Recent work shows that there is a close relationship between adakite and Cu-Cu-Mo epithermal deposit and porphyry copper deposits. We discovered that adakiticss exist in the northwest of VN. Previous studies indicated that its belonged to A type or I type granite. The laser-plasma mass spectrometry (LA-ICP-MS) was used for the zircon U-Pb dating of adakitic in Phan Si Pan zone and the isotope age was obtained to be 38-35 Ma, indicating an Eocene related to the stage of the India-Asia collision. This kind of rocks is represented by granite, and similar in chemical composition to the adakitics rock. In this study we introduce the basic rock types adakitics as well as discuss the existence of this type of research. The discovery may provide a theoretical basis for the prospecting and exploration of the above-mentioned mineral resources in the Phan Si Pan zone in northwestern Vietnam.

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Petrogenesis, Redox State, and Mineralization Potential of Triassic Granitoids in the Mengshan District, South China

Frontiers in Earth Science ◽

10.3389/feart.2021.657618 ◽

2021 ◽

Vol 9 ◽

Author(s):

Yanshen Yang ◽

Xiaofei Pan ◽

Zengqian Hou ◽

Yang Deng ◽

Yongpeng Ouyang ◽

...

Keyword(s):

Trace Elements ◽

South China ◽

Inductively Coupled Plasma ◽

Redox State ◽

Evolutionary Process ◽

Biotite Granite ◽

Nd Isotopes ◽

Inductively Coupled ◽

Fine Grained ◽

Plasma Mass Spectrometry

The Mengshan district is located in the eastern segment of the Jiangnan Orogen in South China. Multi-phase intrusions were emplaced in this district, with the medium-grained porphyritic biotite granite and its marginal phase (fine-grained porphyritic biotite granite) genetically related to metal and non-metal mineralization. In this study, zircon U–Pb ages and trace elements, whole-rock geochemistry, and Nd isotopes were systematically analyzed for medium- and fine-grained porphyritic biotite granite in the Mengshan district, with the aim of elucidating the origin, evolutionary process, redox state, and mineralization competency of the studied granites. The Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA–ICP–MS) zircon U–Pb dating provided a weighted mean age of 226.6 ± 0.5 to 225.9 ± 0.5 Ma for the studied Mengshan granites, synchronous with the late-episode Triassic magmatism-mineralization in South China. The studied Mengshan granites are high-Si and -K, low-P, and weakly peraluminous, exhibiting features of highly evolved I-type granites. The detailed whole-rock geochemistry and Nd isotopes, and zircon trace elements and Hf isotopes demonstrated that the studied Mengshan granites were likely derived from disequilibrium melting of Proterozoic metamorphic basements that were composed of meta-igneous and metasediments and underwent fractional crystallization of plagioclase, K-feldspar, biotite, Fe-Ti oxide, zircon, and apatite. Low whole-rock K/Rb (<150), Nb/Ta (<6), and Zr/Hf (<26) ratios and the metasomatized rim of zircon also suggest that the melt–fluid interaction occurred during the formation of more evolved fine-grained porphyritic biotite granite. The Mengshan granites have a relatively reduced redox state, revealed by their relatively low whole-rock Fe2O3/FeO ratios (mostly < 0.5), zircon Ce4+/Ce3+ ratios (mostly lower than 90), and oxygen fugacity (below ΔFMQ + 1.4). The data in this study indicate that the Mengshan granites, especially the more evolved fine-grained porphyritic biotite granite, are favorable for W, Sn, Mo (<0.3 Mt), and Cu (<1 Mt) mineralization. Moreover, the contact zone between the fine-grained porphyritic biotite granite (or other Triassic granites) and the Permian Maokou Formation (flint-nodule limestone) is a potential target region for wollastonite exploration.

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Preliminary characteristics of rare earth elements and other trace elements in fine-grained deposits from the Triassic-Jurassic transition in the former Mid-Polish Trough

Biuletyn Państwowego Instytutu Geologicznego ◽

10.5604/01.3001.0012.6916 ◽

2018 ◽

Vol 472 (472) ◽

pp. 255-270

Author(s):

Paweł BRAŃSKI

Keyword(s):

Trace Elements ◽

Rare Earth ◽

Rare Earth Elements ◽

Raw Material ◽

Geochemical Data ◽

Fine Grained ◽

Geochemical Study ◽

Icp Ms ◽

The Subject ◽

Siliciclastic Rocks

Fine-grained siliciclastic rocks from the Triassic-Jurassic transition (Rhaetian–Hettangian) in the former Mid-Polish Trough were the subject of the geochemical study at the Polish Geological Institute – National Research Institute in Warsaw. Ninety-four samples of claystones and mudstones from six archived drill cores were analysed by ICP-MS and XRF for rare earth elements (REE) and other trace elements. The results indicate that the sources of most of the claystones and mudstones were sedimentary rocks of the upper continental crust of old cratonic areas, where the protolith had a moderately felsic character. Weathering and recycling processes modified the original chemical composition to some extent. However, during Rhaetian and early Hettangian, some geochemical data in the south-eastern segment of the MPT suggest significant input from a mafic volcanic protolith. Moreover, a clear enrichment in rare-earth elements was observed in few samples, caused by admixtures of accessory minerals (being a main carrier of REE). Nevertheless, based on currently obtained data, the Rhaetian–Hettangian concentrations of REE (and other trace elements) in the MPT are low and they are of scientific indicative significance, not of raw material importance.

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