|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ПсковГУ |
||
The Tigrinoe Greisen Tin–Tungsten Deposit (Primorsky Krai): the Postmagmatic Stage of the Magmatic-Fluid Mineral-Forming Systemстатья
Информация о цитировании статьи получена из
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 23 января 2026 г.
- Авторы: Bortnikov N.S., Aranovich L.Ya, Dubinina E.O., Prokofiev V.Yu, Stavrova O.O., Reutsky V.N., Avdeenko A.S., Kryazhev S.G., Berkovsky E.M., Kossovaa S.A.
- Журнал: Geology of Ore Deposits
- Том: 67
- Номер: 5
- Год издания: 2025
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 543
- Последняя страница: 568
- DOI: 10.1134/S1075701525600422
- Аннотация: To resolve the controversial issue of the origin of fluid(s) and their evolution in magmatic-fluid mineral-forming systems, a comprehensive study of fluid inclusions (FIs) and the isotopic (δ18O, δ2H) composition of granitoid minerals and ore bodies of the Tigrinoe greisen tin–tungsten deposit was carried out. A microthermometric study of FIs in quartz and topaz, along with a study of their gas and bulk chemical composition, showed that T of homogenization and salinity of the aqueous fluid during the formation of ore veins and greisens comprise intervals from ~400 to ~200°C and from 3.5 to 7.5 wt %-eq. NaCl with a noticeable decrease in the salinity of the fluid as T falls. The estimates of ore crystallization conditions based on the FI data were T = 560–230°C, P ≈ 1500–2000 bar, log[fO2] near the fayalite–magnetite–quartz buffer. Data on the bulk composition of the fluid and thermodynamic calculations suggest that the late magmatic high-temperature fluid trapped by inclusions in topaz, enriched in K and Sn, was an active participant in the greisenization process and that the fluid trapped by FIs in quartz was enriched in Na and depleted in Sn and corresponds to equilibrium with feldspars of granitoids at low temperatures. The Sn content in FIs varies from 3 to 3000 ppm; in FIs in quartz it is very low (3–26 ppm, with an average of 13 ± 9 ppm), and in topaz it is high. Rhyolite porphyries are characterized by high δ18O values, indicating the sedimentary nature of their protolith: δ18O(Qz) = 11.4–11.6‰ and δ18O(Fsp) = 8.9–11.0‰; δ18O of micas is from 6.0‰ for the Bolshoi Stock to 9.5–10.1‰ for the remaining intrusion phases. The δ18O values of rhyolite-porphyry minerals indicate short-term external influence of fluid, and the δ2H values of equilibrium fluid (≈–110… ‒130‰) indicate intensive degassing of acidic melts. The ratios of δ18O values in Qz–Znw and Qz–hornfels pairs reflect the pulsed nature of ore formation, generally corresponding to the previously identified stages. The temperature of the oxygen isotope equilibrium in the Qz–Znw pair of ore veins and greisens is T = 400–560°C, and the δ18O and δ2H values of the equilibrium fluid correspond to a magmatic source (8.5–11 and –63…–86‰, respectively). The δ2H values of total hydrogen captured by quartz in ore veins and greisens (‒80…–120‰) indicate a genetic link between the fluid and the products of rhyolite melt degassing, while the δ18O values indicate a local equilibrium between the fluid and the host rocks, which was achieved during its filtration from degassing zones to ore-deposition zones.
- Добавил в систему: Прокофьев Всеволод Юрьевич