Genesis of the supergiant Huayangchuan carbonatite-hosted uranium-polymetallic deposit in the Qinling Orogen, Central China

Zheng, Hui; Chen, Hong‐Yuan; Chao, Wu; Jiang, Hongjun; Gao, Cheng; Kang, Qingqing; Yang, Chunling; Wang, Dequan; Lai, Chun‐Kit

doi:10.1016/j.gr.2020.05.016

Cited by 29 publications

(18 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such multistage, magmatic-hydrothermal uranium mineralization, through the fluid-aided release of uranium from primary uranium-bearing minerals alteration, was also reported in the granite-related uranium deposits in South China [73,87]. Finally, in the Huayangchuan U-polymetallic deposit, Zheng et al [83] proposed that the uranium-rich carbonatite em-placed during the Triassic was ultimately enriched in uranium by the local contamination with Proterozoic uraninite-bearing pegmatite wall rocks, hence demonstrating the potential role of uraninite-bearing pegmatite as a major source of U in the province.…”

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 78%

“…Although we observed relatively limited U remobilization along fractures in the vicinity of uraninite in the Guangshigou pegmatites (Figures 6 and 8), uraninite is an easily leachable mineral by percolation of oxidizing fluids [80][81][82] as indicated by coffinite pseudomorph after uraninite (Figure 6f,g). Therefore, this primary stock of uraninite may have represented a significant source of U for post-Caledonian hydrothermal mineralization that formed in the Qinling Orogen (e.g., Zheng et al [83]), as it was also demonstrated in other major U districts in South China [73,74] or in the European Hercynian Belt [84].…”

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 89%

“…The Qinling Orogenic Belt hosts the most important uranium mineralization belt in central China, which includes various types of uranium deposit (mainly granite-type, pegmatite-type, carbonatite-type and metasedimentary rock-type uranium mineralization) that formed at relatively narrow ages of 400-430 Ma, 200-230 Ma and 100-140 Ma, corresponding to three periods of large-scale tectono-magmatic events (the Caledonian extension-related magmatism, the Indosinian compression process and Yanshanian magmatism) in the Qinling Orogenic Belt [30,85]. For instance, recent studies have revealed that multi-stage uranium mineralization took place within individual deposits in the Qinling Orogen: (i) the Huayangchuan U-polymetallic deposit characterized by Triassic carbonatiterelated primary U mineralization at 220-230 Ma followed by a late stage of hydrothermal mineralization at 120-140 Ma [70,71,83], (ii) the Miaoya REE-Nb-(U) deposit characterized by Caledonian magmatic mineralization at 420-440 Ma followed by hydrothermal remobilization at 220-240 Ma [65,86] and (iii) the Guangshigou U deposit in this study with a Late Caledonian magmatic U mineralization followed by multiple stages of hydrothermal alteration at ca. 310 Ma, ca.…”

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 99%

See 2 more Smart Citations

Uraninite from the Guangshigou Pegmatite-Type Uranium Deposit in the North Qinling Orogen, Central China: Its Occurrence, Alteration and Implications for Post-Caledonian Uranium Circulation

Bonnetti

Liu

et al. 2021

Minerals

View full text Add to dashboard Cite

The Guangshigou deposit is the largest pegmatite-type uranium deposit in the Shangdan domain of the North Qinling Orogenic Belt, which is characterized by the enrichment of uraninite hosted in biotite granitic pegmatites. At Guangshigou, uraninite commonly occurs as mineral inclusions in quartz, K-feldspar and biotite or in interstices of these rock-forming minerals with magmatic characteristics (e.g., U/Th < 100, high ThO2, Y2O3 and REE2O3 contents and low concentrations of CaO, FeO and SiO2). It crystallized at 407.6 ± 2.9 Ma from fractionated calc-alkaline high-K pegmatitic melts under conditions of 470–700 °C and 2.4–3.4 kbar as deduced by the compositions of coexisting peritectic biotite. The primary uranium mineralization took place during the Late Caledonian post-collisional extension in the North Qinling Orogen. After this magmatic event, uraninite has experienced multiple episodes of fluid-assisted metasomatism, which generated an alteration halo of mineral assemblages. The alteration halo (or radiohalo) was the result of the combined effects of metamictization and metasomatism characterized by an assemblage of goethite, coffinite and an unidentified aluminosilicate (probably clay minerals) around altered uraninite. This fluid-assisted alteration was concomitant with the albitization of K-feldspar subsequently followed by the coffinitization of uraninite during the major period of 84.9–143.6 Ma, as determined by U-Th-Pb chemical ages. Further investigations revealed that the metasomatic overprinting on uraninite initially and preferentially took place along microcracks or cavities induced by metamictization and promoted their amorphization, followed by the release of U and Pb from structure and the incorporation of K, Ca and Si from the fluids, finally resulting in various degrees of uraninite coffinitization. The released U and Pb were transported by alkali-rich, relatively oxidizing fluids and then re-precipitated locally as coffinite and an amorphous U-Pb-rich silicate under low to moderate temperature conditions (85–174 °C). The compositional changes in primary uraninite, its structure amorphization together with the paragenetic sequence of secondary phases, therefore, corroborate a combined result of intense metamictization of uraninite and an influx of alkali–metasomatic fluids during the Late Mesozoic Yanshanian magmatic event in the region. Hence, the remobilization and circulation of uranium in the North Qinling Orogen was most likely driven by post-Caledonian magmatism and hydrothermal activities related to large-scale tectonic events. In this regards, Paleozoic pegmatite-type uranium mineralization may represent a significant uranium source for Mesozoic hydrothermal mineralization identified in the Qinling Orogenic Belt.

show abstract

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 78%

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 89%

Section: Processes Responsible For Uraninite Alteration and Radiohalo Formationmentioning

confidence: 99%

See 1 more Smart Citation

Uraninite from the Guangshigou Pegmatite-Type Uranium Deposit in the North Qinling Orogen, Central China: Its Occurrence, Alteration and Implications for Post-Caledonian Uranium Circulation

Bonnetti

Liu

et al. 2021

Minerals

View full text Add to dashboard Cite

show abstract

“…Epidote occurs as dark green tabular and columnar crystals, up to 3 mm in size. The sample of ferriallanite-(Ce) was from the supergiant carbonatite-hosted Huayangchuan ore deposit in the Qinling Orogen (Zheng et al, 2020a). Single crystal diffraction data were collected on Rigaku XtaLAB Synergy-DW diffractometer with microfocus sealed Mo anode tube at 50 kV and 1 mA.…”

Section: Sample Descriptionmentioning

confidence: 99%

Section: Sample Descriptionmentioning

confidence: 99%

Site splitting at M3 in allanite-(Ce)

Shen

Shu

et al. 2022

MinMag

Self Cite

View full text Add to dashboard Cite

We report the crystal structure of allanite-(Ce), with composition (Ca1.0REE0.9□0.1)Σ2.0(Al1.46Fe3+0.52Fe2+0.76Mg0.12Ti0.15)Σ3.01Si3O12(OH) from the Xinfeng rare earth element (REE)-bearing granite in Guangdong Province, China. It has the unit cell a = 8.9550(4) Å, b = 5.77875(16) Å, c = 10.2053(4) Å, β = 114.929(5)° and Z = 2 in space group P21/m and is characterised by site splitting at M3 into M3a and M3b, at a distance of 0.38(3) Å, which are occupied partially by Fe0.764Mg0.12 and Ti0.15, respectively. The structure was determined by single-crystal X-ray diffraction and refined with anisotropic full-matrix least-squares refinement on F2 to R1 = 2.82%, wR2 = 7.77% for 1856 independent reflections (8772 collected reflections). However, M3 splitting is not present in either ferriallanite-(Ce) or epidote, in which M3 is almost fully occupied either by Fe2+ or by Fe3+. Comparisons of bond lengths and volumes in cation polyhedra among allanite-(Ce), ferriallanite-(Ce) and epidote tend to indicate that the essential factor that facilitates site splitting of M3 in allanite-(Ce) is heterovalent substitution and occupation of a crystallographic site between Fe2+(Mg2+/Mn2+)–Al3+(Ti4+), a common phenomenon in minerals, such as the plagioclase series. Fine structure analysis of the M3 split model revealed that deformation of A2 is related closely to distorted M3, which is consistent with Fe2+ incorporation following REE substitution.

show abstract

Textural and compositional evolution of niobium minerals in the Miaoya carbonatite-hosted REE-Nb deposit from the South Qinling Orogen of central China

et al. 2022

View full text Add to dashboard Cite

Genesis of the supergiant Huayangchuan carbonatite-hosted uranium-polymetallic deposit in the Qinling Orogen, Central China

Cited by 29 publications

References 45 publications

Uraninite from the Guangshigou Pegmatite-Type Uranium Deposit in the North Qinling Orogen, Central China: Its Occurrence, Alteration and Implications for Post-Caledonian Uranium Circulation

Uraninite from the Guangshigou Pegmatite-Type Uranium Deposit in the North Qinling Orogen, Central China: Its Occurrence, Alteration and Implications for Post-Caledonian Uranium Circulation

Site splitting at M3 in allanite-(Ce)

Textural and compositional evolution of niobium minerals in the Miaoya carbonatite-hosted REE-Nb deposit from the South Qinling Orogen of central China

Contact Info

Product

Resources

About