Jun-Ying Ding

The Evolution of Ore‐forming Fluid of Maoping Lead‐Zinc Deposit, Zhaotong in Northeast Yunnan: the Evidence of Sphalerite‐hosted Fluid Inclusions

The Maoping zinc-lead deposit is one of the typical zinc-lead deposits in Northeast Yunnan District, located in the sagged Yunnan basin at the middle end of the Yangtze platform. This district has been the focus of extensive and intensive research for more than 40 years on its geology, geochemistry, geochronology, tectonics, ore-genesis and ore-prospecting. As ore-prospecting on deep orebody at recent years, the deposit has been a large-type one in this district. Prior to this study, many papers have been published on ore-prospecting, geology, tectonics, fluid inclusion studies of the Maoping lead-zinc deposit (Zou et al., 2004; Han et al., 2007; Hu et al., 2003; Hu Bin, 2004; Wang et al., 2009; Shentu et al., 2011). The fluid inclusion study was restricted to quartz, dolomite and calcite which paragenetic with ore minerals (Han et al., 2007).

Geology, mineral paragenesis and fluid inclusion studies of the Yueyang Ag-Au-Cu deposit, South China: implications for ore genesis and exploration

The Yueyang epithermal Ag-Au-Cu deposit is located in the Zijinshan ore district in western Fujian Province, South China. Orebodies are predominately hosted by the Jurassic Zijinshan granite batholith and controlled by a group of NW-trending faults. Roughly all minerals were deposited in a single extended period, and three stages can be further defined: (1) the early sphalerite stage; (2) the base metal-silver stage; and (3) the post-mineralization stage. Microthermometric measurements on quartz- and sphalerite-hosted, liquid-rich fluid inclusions indicate that mixing and dilution of the ore forming fluids took place from early to late stages. However, fluid boiling may locally occur and lead to silver participation, as suggested by the presence of fluid inclusion assemblage consisting of coexisting liquid-rich and vapour-rich inclusions, and also indicated by adularia in Ag-bearing veins and the breccia type ore of bonanza grade. Compared with typical low-sulphidation epithermal deposits, the higher Ag/Au ratios and fluid salinities, Fe-poor sphalerite and large proportion of sulphide minerals suggest that the Yueyang deposit is best classified as an intermediate-sulphidation epithermal deposit. Since intermediate-sulphidation epithermal deposits favour a magmatic affinity and usually exhibit spatial and temporal association with high-sulphidation and porphyry deposits, mineral exploration at the adjacent area of the Yueyang deposit is promising.

Mapping of fluid, alteration and soil geochemical anomaly as a guide to regional mineral exploration for the Dehua gold orefield of Fujian Province, southeast China

The Dehua gold ore-field, located in the central-eastern Fujian Province, SE China, is an important part of the renowned Dehua-Youxi-Yongtai gold ore production area. The ore-field contains several low-intermediate sulphidation epithermal gold deposits and numerous gold-bearing mineralized bodies. The extensive presence of intensely altered rocks, suitable structural environment, acidic intrusions and volcanic-subvolcanic rocks indicates an important potential for epithermal gold mineralization. In this work, fluid inclusion homogenization temperature and alteration mapping was carried out by fluid inclusion microthermometry in quartz and identification of alteration minerals closely related to the known mineralization. The result shows the trend of temperature contour curves as well as the shape of low argillic alteration zones implying that the area north of Qiucun might be profitable for future mineral exploration. The fluid and alteration mapping, in combination with soil geochemical mapping, defines the architecture of the epithermal-porphyry ore-forming system in the Dehua ore-field. Finally, the presence of intensely altered areas, high value zones of hydrothermal fluid flows and combined anomaly areas of multi-element association indicate that the region north of Qiucun has an important potential as a preferred target area for gold prospecting in the Dehua ore-field.

Fluid Inclusions and Isotopes Constraining the Ore Genesis of the Neoproterozoic Jinshan Orogenic Gold Deposit, South China

The Jinshan gold deposit is located in the famous Dexing copper-gold polymetallic district in eastern China. This polymetallic district consists of the Neoproterozoic Jinshan gold deposit (180 tons of Au), the Middle Jurassic Dexing porphyry Cu-Au-Mo deposits (6 Mt of Cu and 138 tons of Au) and the Middle Jurassic Yinshan Cu-Au-PbZn-Ag deposit (1.0 Mt of Cu and 107 tons of Au). Ore genesis of the Jinshan gold deposit is hotly debated. Some researchers proposed that it was a typical Neoproterozoic orogenic gold deposit (Li et al., 2010), but others pointed out that it belonged to Jurassic Dexing porphyryepithermal ore system (Mao et al., 2011).