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The Dongmozhazhua deposit, the largest Pb-Zn deposit in south Qinghai, China, is stratabound, carbonate-hosted and associated with epigenetic dolomitization and silicification of Lower-Middle Permian-Upper Triassic limestones in the hanging walls of a Cenozoic thrust fault system. The mineralization is localized in a Cenozoic thrust-folded belt along the northeastern edge of the Tibetan plateau, which was formed due to the India-Asia plate collision during the early Tertiary. The deposit comprises 16 orebodies with variable thicknesses (1.5-26.3 m) and lengths (160-1820 m). The ores occur as dissemination, vein, and breccia cement. The main sulfide assemblage is sphalerite + galena + pyrite + marcasite ± chalcopyrite ± tetrahedrite, and gangue minerals consist mainly of calcite, dolomite, barite, and quartz. Samples of pre- to post-ore stages calcite yielded δ13C and δ18O values that are, respectively, similar to and lower than those yielded by the host limestones, suggesting that the calcite formed from fluids derived from carbonate dissolution. Fluid inclusions in calcite and sphalerite in the polymetallic sulfidization stage mostly comprise liquid and gas phases at room temperature, with moderate homogenization temperatures (100-140°C) and high salinities (21-28 wt% NaCl eq.). Micro-thermometric fluid inclusion data point to polysaline brines as ore-forming fluids. The δD and δ18O values of ore fluids, cation compositions of fluid inclusions, and geological information suggest two main possible fluid sources, namely basinal brines and evaporated seawater. The fluid inclusion data and regional geology suggest that basinal brines derived from Tertiary basins located southeast of the Dongmozhazhua deposit migrated along deep detachment zones of the regional thrust system, leached substantial base metals from country rocks, and finally ascended along thrust faults at Dongmozhazhua. There, the base-metal-rich basinal brines mixed with bacterially-reduced H2S-bearing fluids derived from evaporated seawater preserved in the Permo-Triassic carbonate strata. The mixing of the two fluids resulted in Pb-Zn mineralization. The Dongmozhazhua Pb-Zn deposit has many characteristics that are similar to MVT Pb-Zn deposits worldwide. [ABSTRACT FROM AUTHOR]

The article offers information on the SinoProbe, a deep exploration and multidisciplinary earth science research program in China, which was successfully conducted scientific deep drilling, named ZK01 in the Zhuanqiao district of the Luzong Basin. It mentions that three types of fluid inclusions including liquid-rich, gas-rich and daughter mineral-bearing fluid inclusions was observed. It also mentions that boiling are occurred in fluid evolution changing physical and chemical state.

The article discusses the fluid inclusion and isotopic characteristics of Dongleiwan Skarn Deposit in Jiangxi Province. Topics discussed include tectonic positions of Dongleiwan deposits; main metal mineral ores of deposits such as chalcopyrite, pyrite and bornite; and classification of main mineralization stage into four categories.

• Early fluids and metals are sourced from the intermediate-level magma chamber. • Enrichment of Mo, Pb, Zn records a greater proportion of ancient crustal material. • That variability of metal contents is a better predictor of mineralization potential. The large Bangpu Mo–Cu–Pb–Zn deposit, is a Mo-rich (~0.089%), Cu-poor (~0.32%) porphyry–skarn deposit located in the northeastern Gangdese porphyry copper belt (GPCB), Southern Tibet. In this study, LA – ICP – MS data for fluid inclusions and quartz formed during different stages of the mineralization are used to (1) constrain changes in fluid composition during mineralization; (2) infer the origin, transport pathways, and conditions of ore precipitation; and (3) explore the influence of magma chamber on fluid exsolution and shallow mineralization. The Cu content of the vapor-rich (VL) inclusions is higher than that of the halite-bearing (LVH) inclusions, while the Mo, Pb, and Zn contents of the VL and LVH inclusions are similar, indicating that Mo, Cu, Pb, and Zn had a common source, which is inferred to be the intermediate-level magma chamber. The metal contents of fluid inclusions in the early stage potassic alteration-related vein (A vein) and later stage sericitic alteration-related vein (B vein) are similar but variable, implying the intermediate-level magma chamber was too small to form a large stable fluid system. The enrichment of Mo, Pb, and Zn in the Bangpu deposit relative to other porphyry deposits in the GPCB is related to the participation of ancient crustal material. A comparison of our results with those from super-large porphyry Cu deposits elsewhere indicates that metal-rich fluids are not the sole factor to form ore deposits, and the variability of metal contents in the early exsolved fluids is a better predictor of mineralization potential than absolute metal concentrations. [ABSTRACT FROM AUTHOR]