Genesis of Dulong Sn-Zn-In Polymetallic Deposit in Yunnan Province, South China: Insights from Cassiterite U-Pb Ages and Trace Element Compositions

The Dulong Sn-Zn-In polymetallic deposit in the Yunnan province, SW China, hosts a reserve of 5.0 Mt Zn, 0.4 Mt Sn, and 7 Kt In. It is one of the most important polymetallic tin ore districts in China. Granites at Dulong mining area include mainly the Laojunshan granite (third phase), which occurs as quartz porphyry or granite porphyry dikes in the Southern edge of the Laojunshan intrusive complex. Granites of phases one and two are intersected at drill holes at depth. There are three types of cassiterite mineralization developed in the deposit: cassiterite-magnetite ± sulfide ore (Cst I), cassiterite-sulfide ore (Cst II) within the proximal skarn in contact with the concealed granite (granites of phases one to two and three), and cassiterite-quartz vein ore (Cst III) near porphyritic granite. Field geology and petrographic studies indicate that acid neutralising muscovitization and pyroxene reactions were part of mechanisms for Sn precipitation resulting from fluid-rock interaction. In situ U–Pb dating of cassiterite samples from the ore stages of cassiterite-sulfide (Cst II) and Cassiterite-quartz vein (Cst III) yielded Tera-Wasserburg U–Pb lower intercept ages of 88.5 ± 2.1 Ma and 82.1 ± 6.3 Ma, respectively. The two mineralization ages are consistent with the emplacement age of the Laojunshan granite (75.9–92.9 Ma) within error, suggesting a close temporal link between Sn-Zn(-In) mineralization and granitic magmatism. LA-ICPMS trace element study of cassiterite indicates that tetravalent elements (such as Zr, Hf, Ti, U, W) are incorporated in cassiterite by direct substitution, and the trivalent element (Fe) is replaced by coupled substitution. CL image shows that the fluorescence signal of Cst I–II is greater than that of Cst III, which is caused by differences in contents of activating luminescence elements (Al, Ti, W, etc.) and quenching luminescence element (Fe). Elevated W and Fe but lowered Zr, Hf, Nb, and Ta concentrations of the three type cassiterites from the Dulong Sn-Zn-In polymetallic deposit are distinctly different from those of cassiterites in VMS/SEDEX tin deposits, but similar to those from granite-related tin deposits. From cassiterite-magnetite ± sulfide (Cst I), cassiterite-sulfide ore (Cst II), to cassiterite-quartz vein ore-stage (Cst III), high field strength elements (HFSEs: Zr, Nb, Ta, Hf) decrease. This fact combined with cassiterite crystallization ages, indicates that Cst I–II mainly related to concealed granite (Laojunshan granites of phases one and two) while Cst III is mainly related to porphyritic granite (Laojunshan granites of phase three).

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Trace element geochemistry of magnetite from the giant Beiya gold-polymetallic deposit in Yunnan Province, Southwest China and its implications for the ore forming processes

Ore Geology Reviews ◽

10.1016/j.oregeorev.2017.09.007 ◽

2017 ◽

Vol 91 ◽

pp. 477-490 ◽

Cited By ~ 13

Author(s):

Xiaoming Sun ◽

Hai Lin ◽

Yu Fu ◽

Dengfeng Li ◽

Pete Hollings ◽

...

Keyword(s):

Trace Element ◽

Yunnan Province ◽

Southwest China ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

Polymetallic Deposit

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Geochronology and trace element geochemistry of titanite in the Machangqing Cu-Mo-dominated polymetallic deposit, Yunnan Province, southwest China

Journal of Asian Earth Sciences ◽

10.1016/j.jseaes.2018.03.014 ◽

2018 ◽

Vol 158 ◽

pp. 398-414 ◽

Cited By ~ 7

Author(s):

Yu Fu ◽

Xiaoming Sun ◽

Pete Hollings ◽

Dengfeng Li ◽

Tianjian Yang

Keyword(s):

Trace Element ◽

Yunnan Province ◽

Southwest China ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

Polymetallic Deposit

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Spatial distribution characteristics of trace element content in tobacco and soil in Luliang of Yunnan province and the main influencing factors

JOURNAL OF HUNAN AGRICULTURAL UNIVERSITY ◽

10.3724/sp.j.1238.2012.00235 ◽

2013 ◽

Vol 38 (3) ◽

pp. 235-240

Author(s):

Yue ZHAO ◽

Ji-heng ZHOU ◽

Xi-yu CHEN ◽

Chao-ke LIU ◽

Zheng-yan ZHANG ◽

...

Keyword(s):

Spatial Distribution ◽

Trace Element ◽

Influencing Factors ◽

Yunnan Province ◽

Trace Element Content ◽

Element Content ◽

Distribution Characteristics ◽

Spatial Distribution Characteristics

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MAGMA-WALL ROCK INTERACTION IN THE ST FRANCOIS MOUNTAINS, MISSOURI: UNRAVELLING MAGMATIC ARCHITECTURE USING MICROSTRUCTURES AND TRACE ELEMENT GEOCHEMISTRY

10.1130/abs/2020sc-343245 ◽

2020 ◽

Author(s):

Gary S. Michelfelder ◽

◽

Kimberly LaRue

Keyword(s):

Trace Element ◽

Wall Rock ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

Rock Interaction

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Magnetite texture and trace-element geochemistry fingerprint of pulsed mineralization in the Xinqiao Cu-Fe-Au deposit, Eastern China

American Mineralogist ◽

10.2138/am-2020-7414 ◽

2020 ◽

Vol 105 (11) ◽

pp. 1712-1723

Author(s):

Yu Zhang ◽

Pete Hollings ◽

Yongjun Shao ◽

Dengfeng Li ◽

Huayong Chen ◽

...

Keyword(s):

Trace Element ◽

Triple Junction ◽

Eastern China ◽

Black Shales ◽

Hydrothermal Fluids ◽

Oscillatory Zoning ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

Rock Interaction ◽

Multiple Pulses

Abstract The origin of stratabound deposits in the Middle-Lower Yangtze River Valley Metallogenic Belt (MLYRB), Eastern China, is the subject of considerable debate. The Xinqiao Cu-Fe-Au deposit in the Tongling ore district is a typical stratabound ore body characterized by multi-stage magnetite. A total of six generations of magnetite have been identified. Mt1 is commonly replaced by porous Mt2, and both are commonly trapped in the core of Mt3, which is characterized by both core-rim textures and oscillatory zoning. Porous Mt4 commonly truncates the oscillatory zoning of Mt3, and Mt5 is characterized by 120° triple junction texture. Mt1 to Mt5 are commonly replaced by pyrite that coexists with quartz, whereas Mt6, with a fine-grained foliated and needle-like texture, commonly cuts the early pyrite as veins and is replaced by pyrite that coexists with calcite. The geochemistry of the magnetite suggests that they are hydrothermal in origin. The microporosity of Mt2 and Mt4 magnetite, their sharp contacts with Mt1 and Mt3, and lower trace-element contents (e.g., Si, Ca, Mg, and Ti) than Mt1 and Mt3 suggest that they formed via coupled dissolution and reprecipitation of the precursor Mt1 and Mt3 magnetite, respectively. This was likely caused by high-salinity fluids derived from intensive water-rock interaction between the magmatic-hydrothermal fluids associated with the Jitou stock and Late Permian metalliferous black shales. The 120° triple junction texture of Mt5 suggests it is the result of fluid-assisted recrystallization, whereas Mt6 formed by replacement of hematite as a result of fracturing. The geochemistry of the magnetite suggests that the temperature increased from Mt2 to Mt3 and implies that there were multiple pulses of fluids from a magmatic-hydrothermal system. Therefore, we propose that the Xinqiao stratiform mineralization was genetically associated with multiple influxes of magmatic hydrothermal fluids derived from the Early Cretaceous Jitou stock. This study demonstrates that detailed texture examination and in situ trace-elements analysis under robust geological and petrographic frameworks can effectively constrain the mineralization processes and ore genesis.

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Stable isotope and Fluid Inclusion constraints on the Source and Evolution of Ore Fluids in the Xiuwacu W-Mo Granite-related Quartz-vein deposit, Yunnan Province, China

Ore Geology Reviews ◽

10.1016/j.oregeorev.2021.104245 ◽

2021 ◽

pp. 104245

Author(s):

Xiang-Fei Zhang ◽

Wen-Chang Li ◽

Zhen Yang ◽

Yu-Qin Wang

Keyword(s):

Stable Isotope ◽

Fluid Inclusion ◽

Quartz Vein ◽

Yunnan Province ◽

Vein Deposit

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Trace Element Geochemistry and Mineral Inclusions Constraints on the Petrogenesis of a Marble–Hosted Ruby Deposit in Yunnan Province, China

The Canadian Mineralogist ◽

10.3749/canmin.2000054 ◽

2021 ◽

Author(s):

Wenqing Huang ◽

Pei Ni ◽

Ting Shui ◽

Junyi Pan ◽

Mingsen Fan ◽

...

Keyword(s):

Trace Element ◽

Inductively Coupled Plasma ◽

Yunnan Province ◽

Geographic Origin ◽

Source Rocks ◽

Trace Element Geochemistry ◽

Mineral Inclusion ◽

Element Geochemistry ◽

Inductively Coupled ◽

Mineral Inclusions

Abstract Primary rubies in the Ailao Shan of Yunnan Province, China, are found in three layers of marble. However, the origin and source rocks of placer rubies in the Yuanjiang area remains unclear. Trace element geochemistry and inclusion mineralogy within these materials can provide information on their petrogenesis and original source. Zircon, rutile, mica group minerals, titanite, and apatite group minerals were the main solid inclusions identified within the placer Yuanjiang rubies, along with other mineral inclusions such as pyrite, pyrrhotite, plagioclase group minerals, and scapolite group minerals. Laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) measurements showed that the placer rubies are characterized by average values of Mg (31 ppmw), Ti (97 ppmw), V (77 ppmw), Cr (3326 ppmw), Fe (71 ppmw), and Ga (66ppmw). A trace-element oxide diagram, Fe values (<350 ppmw), and the mineral inclusion assemblage suggest marble sources for the placer ruby. Therefore, the Yuanjiang rubies (both primary and placer) are metamorphic, and this fits well with the observations that skarn and related minerals are mostly absent in this deposit. Yuanjiang rubies can be readily separated from the high-iron rubies of different geological types by their Fe content (<1000 ppmw). The discriminators Mg, Ga, Cr, V, Fe, and Ti have potential in separating Yuanjiang rubies from some other marble-hosted deposits, such as Snezhnoe. Nevertheless, geographic origin determination remains a challenge when considering the similarities in compositional features between the Yuanjiang rubies and rubies from some other marble-hosted deposits worldwide (e.g., Luc Yen). The presence of kaolinite group minerals and clusters of euhedral, prismatic zircon crystals in ruby suggest a Yuanjiang origin.

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