Wang Qingfei

Random Difference of the Trace Element Distribution in Skarn and Marbles from Shizishan Orefield, Anhui Province, China

Abstract Spatial distribution patterns of element concentrations can reflect the information of the mineralization processes. Both the Hurst exponent calculated by R / S analysis and the generalized fractal dimension calculated by using the multifractal model are important parameters for describing the spatial distribution of elements. Five long drill holes, named as M1, S1, S2, S3, and S4, have been selected in the Shizishan skarn orefield in Tongling, Anhui Province, China. Marbles are well developed around M1 and skarn rocks are largely distributed along S1, S2, S3, and S4 drill holes. The drill holes were sampled evenly with an interval of 10 m and 16 trace elements have been measured. The mean of the Δ D(q) (the height of the generalized dimension spectrum) in the M1 drill hole is the lowest. In addition, the mean of the Hurst exponents of the 16 elements in the M1 drill hole is also much smaller than that of S1, S2, S3, S4 drill holes, which is in accordance with the analysis of the generalized dimension. It is indicated by the generalized dimension and Hurst exponent that the distribution of trace elements in the marbles is more random than that in the skarn. The result suggests that the mineralization process can change the randomness and persistence features of the element distribution.

Metallogenic epoch and genesis of the gold deposits in Jiaodong Peninsula, Eastern China: a regional review

Abstract Gold deposits are characterized by multi-sources, superimposition, large scale and temporal-spatial concentration in Jiaodong Peninsula, Eastern China. In this paper, we review the history and the development of the study on metallogenic chronology and genesis of gold deposits, summarize the main features of superimposed metallogenesis, provide evidence of the Mesozoic complex metallogenic system, and point out some problems for further research of Jiaodong gold deposit cluster from a regional view. Although gold deposits are different in genetic types, ore-forming materials and geological settings, our research indicates that the accumulation and emplacement of the ore-forming materials are temporally-spatially concentrated on a large scale, and the main metallogenic epoch of Jiaodong gold deposits was concentrated in Mesozoic. Metallogenic chronology and geological-geochemical data indicate that there are two periods of gold mineralizations occurred in 130–110 Ma and 90–80 Ma respectively in Ji...

Decrepitation Thermometry and Compositions of Fluid Inclusions of the Damoqujia Gold Deposit, Jiaodong Gold Province, China: Implications for Metallogeny and Exploration

Abstract The recently discovered Damoqujia gold deposit is a large shear zone-hosted gold deposit of disseminated sulphides located in the north of the Zhaoping fault zone, Jiaodong gold province, China. In order to distinguish the temperature range of cluster inclusions from different mineralization stages and measure their compositions, 16 fluid inclusions and 5 isotopic geochemistry samples were collected for this study. Corresponding to different mineralization stages, the multirange peaks of quartz decrepitation temperature (250–270, 310–360 and 380–430 °C) indicate that the activity of ore-forming fluids is characterized by multistage. The ore-forming fluids were predominantly of high-temperature fluid system (HTFS) by CO2-rich, and SO42--K+ type magmatic fluid during the early stage of mineralization and were subsequently affected by low-temperature fluid system (LTFS) of CH4-rich, and Cl−-Na+/Ca2+ type meteoric fluid during the late stage of mineralization. Gold is transferred by Au-HS− complex in the HTFS, and Au-Cl− complex can be more important in the LTFS. The transition of fluids from deeper to shallow environments results in mixing between the HTFS and LTFS, which might be one of the most key reasons for gold precipitation and large-scale mineralization. The ore-forming fluids are characterized by high-temperature, strong-activity, and superimposed mineralization, so that there is a great probability of forming large and rich ore deposit in the Damoqujia gold deposit. The main bodies are preserved and extend toward deeper parts, thereby suggesting a great potential in future.

Crust-mantle structures and gold enrichment mechanism of mantle fluid system

Gold enrichment mechanism of ore-forming fluid is the essence of gold metallization. This paper summarizes the distinguishing symbols of mantle fluid and effect of crust-mantle structure on fluid movement. Fluid moving processes include osmosis, surge, gas-liquid alternation and mutation of fluid speed. During fluid movement, gold will be enriched gradually. Finally, a layered circulatory system is illustrated in this paper.

Origin of Gold-Bearing Fluid and Its Initiative Localization Mechanism in Xiadian Gold Deposit, Shandong Province

The composition of quartz inclusions and trace elements in ore indicate that gold bearing fluid in the Xiadian gold deposit, Shandong Province, stemmed from both mantle and magma, belonging to a composite origin. Based on theoretical analysis and high temperature and high pressure experimental studies, gold-bearing fluid initiative localization mechanism and the forming environment of ore-host rocks are discussed in the present paper. The composite fluid extracted gold from rocks because of its expanding and injecting forces and flew through ore-conducive structures, leading to the breakup of rocks. The generation of ore-host faults and the precipitation of gold-bearing fluid occurred almost simultaneously. This study provides further information about the relationships between gold ore veins and basic-ultrabasic vein rocks and intermediate vein rocks, the spatial distribution of gold ore veins and the rules governing the migration of ore fluids.