Samples of active chimneys, chimney flanges and massive sulfides from the Daiyon-Yonaguni Knoll hydrothermal field are composed of major barite and minor stibnite and orpiment. Barite is inferred to precipitate from focused-discharge fluids composed of >40% hydrothermal end-member fluid at T = 100-240°C, whereas the stibnite and orpiment are later and lower temperature precipitates. The hydrothermal fluids from this field were subject of sub-seafloor boiling and phase separation and, consequently, are brine-rich depleted in volatile and enriched in non-volatile elements. Boiling and phase separation exerted major control on the rare earth elements (REE) partitioning in the vent fluids: high-chlorinity high-temperature fluids were enriched in light REE and low-chlorinity low-temperature fluids were enriched in heavy REE. Y/Ho molar ratio and Ce anomaly of the vent fluids suggest that the seawater has not completely reacted with the basement rocks and has not equilibrated with them. The trace element concentrations in the hydrothermal deposits suggest a complex interplay among hydrothermal, hydrogenetic and microbial processes. Sulfur isotope composition of the sulfides suggests that the sulfide S is a mixture of both basement rock and seawater S with a higher proportion of the basement rock S. The sulfate dissolved in the fluids was subjected to reduction during a slow mixing of hydrothermal fluid and seawater within the chimney walls of the Tiger and Abyss vents and this resulted in a heavy S-isotope composition of the vent fluid sulfate. Lead isotope composition of the hydrothermal deposits indicates mixing relationships suggesting that Pb and potentially other metals with similar geochemical behavior were derived from two or three sources. The Pb isotopes in the hydrothermal deposits imply that an enriched source, either sediments or extended continental lithosphere, and a depleted source, potentially back-arc mafic volcanics, are present in the area of Daiyon-Yonaguni Knoll. Filamentous orpiment found in the deposits is supposed to be either heavily mineralized fungal hyphae or pure abiogenic biomorphs. Presence of carbonaceous matter on and around the orpiment filaments suggests for microbial activity during filament formation. The filaments experienced temperature of 209.1±37.1°C which falls within the temperature range of the Daiyon-Yonaguni Knoll vent fluids. Stability phase diagrams modeling reveals that the stability of stibnite does not depend on the vent fluid chlorinity, but depends on the vent fluid temperature: the area of stibnite stability increases with decreasing vent fluid temperature and results in stibnite precipitation at low log₁₀a of Sb₂S₄^2- and less reduced environment (Eh still <0). Orpiment is stable in a wide range of log₁₀a of H₂AsO₄^-, in reduced conditions and at high S activity. Barite is stable in wide range of log₁₀a of Ba²⁺ and precipitates in slightly reduced to slightly oxic conditions.

Daiyon-Yonaguni Knoll 热液田的活动烟囱、烟囱法兰和块状硫化物样品由主要的重晶石和次要的辉锑矿和雌蕊组成。重晶石被推断为在 T = 100-240°C 时从由 >40% 热液端元流体组成的集中放电流体中沉淀出来，而辉锑矿和雌黄晶是较晚和较低温度的沉淀物。来自该油田的热液流体经历了海底沸腾和相分离，因此富含盐水，缺乏挥发性元素，富含非挥发性元素。沸腾和相分离主要控制排放流体中稀土元素 (REE) 的分配：高氯高温流体富集轻稀土元素，低氯低温流体富集重稀土元素。喷口流体的 Y/Ho 摩尔比和 Ce 异常表明海水没有与基底岩石完全反应，也没有与其平衡。热液沉积物中的微量元素浓度表明热液、加氢和微生物过程之间存在复杂的相互作用。硫化物的硫同位素组成表明硫化物 S 是基岩和海水 S 的混合物，其中基岩 S 的比例较高。溶解在流体中的硫酸盐在热液流体和海水的缓慢混合过程中被还原Tiger 和 Abyss 喷口的烟囱壁内，这导致喷口流体硫酸盐的重 S 同位素组成。热液矿床的铅同位素组成表明混合关系表明 Pb 和可能具有相似地球化学行为的其他金属来自两个或三个来源。热液矿床中的 Pb 同位素表明在 Daiyon-Yonaguni Knoll 地区存在富集源（沉积物或扩展大陆岩石圈）和贫源（可能是弧后镁铁质火山）。在沉积物中发现的丝状雌蕊被认为是高度矿化的真菌菌丝或纯非生物的生物形态。雌蕊丝上和周围存在碳质物质表明在丝形成过程中存在微生物活动。细丝的温度为 209.1±37.1°C，属于 Daiyon-Yonaguni Knoll 排放流体的温度范围。_10a的 Sb ₂ S ₄ ^2-和更少的还原环境（Eh 仍 <0）。雌黄在H ₂ AsO ₄ ^{-的 log} ₁₀ a范围很宽，在还原条件和高 S 活度下是稳定的。重晶石在Ba ^{2+的 log} ₁₀ a 的宽范围内是稳定的，并且在轻微还原到轻微有氧的条件下沉淀。