Significance of quartz REE geochemistry, Shihu gold deposit, western Hebei Province, North China, using LA-ICP-MS

Cao, Yue; Li, Shengrong; Yao, Meijuan; Zhang, Huafeng

doi:10.1007/s11707-010-0136-z

Cited by 4 publications

(1 citation statement)

References 15 publications

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“…The U/Th ratio range (0.1-1.1) in quartz veins also indicates an oxidized and neutral environment [44]. The Y/Ho value is applied to interpret sources of ore-bearing fluids [45,46]. The Y/Ho ratio in quartz veins from all of the studied deposits varies from 29 to 41, which is overlapped by the range of Y/Ho ratios in rocks of the Khudolaz complex [47].…”

Section: Geochemical Evolution Of Quartz Veinsmentioning

confidence: 92%

Origin and Evolution of Ore-Forming Fluids at the Small-Sized Gold Deposits in the Khudolaz Area, Southern Urals

et al. 2023

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Lode gold deposits are widespread in orogenic belts of various ages and are a valuable gold source, but their genesis remains debatable. The close relationship between native gold and quartz was considered a reason to search for acid-magmatic sources of heat and fluids (i.e., granite intrusions), while small gabbro bodies were often ignored. Six minor gold deposits associated with NE-strike faults were studied in the Khudolaz area of the South Urals (Tukan, Bilyan-Tau, Fazly-Tau, Muildy-Tamak, Alasiya-II and Isyanbet-I). It was established, for the first time, that all of the studied deposits are similar geologically but differ in mineralogical diversity of ore-bearing quartz veins, which is due to the different composition of host rocks and ore-bearing intrusions of the Khudolaz (325–329 Ma, U-Pb) and the Ulugurtau (321 ± 15 Ma, Sm-Nd) ultramafic-mafic complexes. Results of the geochemical study of quartz veins (ICP MS) and their fluid inclusions (microthermometry, gas chromatography) showed that native gold was mostly precipitated at temperatures of 230–330 °C from a low- to moderate-saline (8–12 wt.% NaCl-eq.) H2O–CO2–CH4-bearing fluid, when weakly oxidized or near-neutral conditions, were replaced by reducing ones. No significant differences between barren milky white and ore-bearing brownish quartz veins were defined, which indicates their common formation settings and an impulse pattern of vein injection. The stable pattern of the fluid salinity, along with low hydrocarbon and N2 contents, as well as a narrow range of δ18O values, indicate a prevailing magmatogenic source with a certain influence of host rocks but without the influence of meteoric waters. Based on the presented data, the studied deposits were attributed to the epizonal orogenic type. This study shows the formation of lode gold deposits is possible without the participation of granite massifs.

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