摘要
对金家庄金矿田氧、氢、硫、铅等稳定同位素地质研究后指出:成矿物质主要来源于古老岩石重熔物质和变质岩类;成矿溶液主要来源于岩浆水,其次是变质水,并有一定量大气降水。
Hydrogen, oxygen, sulfur and lead stable isotopic studies were conducted for four gold deposits (Hougou, Taogou, Beigou and Dabeiyan) in the Jinjiazhuang gold orefield.
δ^(18)O values of the ore-forming solutions vary in the range of 1.26‰～7.39‰, with the population mean close to the lowest value of magmatic water;δD values range from -116‰ to -80‰, which somewhat deviate from the isotopic composition of magmatic water, suggesting the addition of some meteoric water.
δ^(34)S values of Dabeiyan, Beigou and Taogou are 0.l‰～4.1‰, implying that these deposits had similar physicochemical conditions and identical magmatic source.δ^(34)S values of Hougou are -8.2‰～15.9‰, indicating that the ore-forming solutions came from rainwater and underground hot water and absorbed, fairly abundant light sulfur, which then took part in the ore-forming process.
^(206)Pb/^(204)Pb=16.443～17.721, ^(207)Pb/^(204)Pb=15.176～15.525, and ^(208)Pb/^(204)Pb=36.46～37.713, mostly located near the mean lead evolutionary curve of the mantle and the lower crust in B.R.Doe's and Zatman's structural distribution diagram.μ values are below 9.58, suggesting that ore-forming substances were derived from the lower crust or the upper mantle.
The difference in stable isotopic characteristics between various gold deposits in the Jinjiazhuang gold orefield suggests the difference in percolation form of meteoric water and in geology of ore deposits.
Ore-forming substances of the Jinjiazhuang gold orefield came from the anatectic magma, which formed rocks and ore deposits in situ or after migrating to suitable geological structures.In the process of constant circulation, its ore-forming fluids got mixed with solutions that carried ore substances extracted from metamorphic rocks by meteoric water and later precipitated in different geologic and structural environments, forming various types of gold deposits.
出处
《矿床地质》
CAS
CSCD
北大核心
1992年第4期341-350,共10页
Mineral Deposits
