中文摘要:得田沟金矿床是受韧性剪切带控制的石英脉-蚀变岩型金矿床。容矿岩石主要为太古宙受混合岩化的角闪岩相变质岩系。矿石矿物主要为黄铁矿、方铅矿、闪锌矿、黄铜矿、碲铅矿及金、银(铋)的单质和化合物等，脉石矿物主要为石英、方解石、绿泥石、绿帘石、绢云母，阳起石等。Au、Ag(Bi)主要呈细粒自然金、自然银、碲金银矿、针碲金银矿、碲银矿、六方碲银矿、螺状硫银矿、未定名矿物AgS1+x，Te1-x和Bi5Te6存在。自然金与方铅矿、黄铜矿及Pb、Au、Ag及Bi的碲化物共生，或充填石英及黄铁矿的微裂隙。Au的沉淀晚于黄铁矿、早于闪锌矿，与方铅矿、黄铜矿及碲铅矿的沉淀基本同步。
Abstract:The Detiangou ore deposit consists of gold-polymetallic quartz veins occurring in Archean migmatized biotite leucogranulite, biotite leptynite, amphiBole-biotite plagioclase gneiss, plagioclase amphibolite and hornblendite. The major ore veins are confined to the ductile shear zones near the ore-control fault(F1). The ore deposit is a hydrothermal filling veinlike one. The ore minerals are mainly pyrite, galena, sphalerite, chalcopyrite, altaite, and gold-silver minerals, associated with small amounts of arsenopyrite, bornite, magnetite, pyrrhotite and bismuth minerals; the gangue minerals include quartz, calcite, chlorite, epidote, sericite and actinolite. The contents of major and minor elements in main sulfides are shown in Table 1. These sulfide minerals contain high but varying amounts of Au, Ag and Te, related chiefly to the nonuniform distribution of gold, silver and telltirium minerals in them. Gold, silver(bismuth) occur mainly as fine-grained native gold, native silver(Table 2), petzite, sylvanite, hessite, stuetzite, argenrite, unnamed mineral AgS1+xTe1-x, and unnamed Bi3Bi2Te6(Table 3). Native gold is associated with galena, chalcopyrite and lead-gold-silver-bismuth tellurides or fills microfissures of quartz and pyrite(Plate I，1-8), whereas silver minerals, except AgS1+xTe1-x, commonly occur as microgranular aggregates in quartz rimming polymetallic sulfides, suggesting that gold, silver and bismuth minerals, galena, chalcopyrite and sphalerite were formed later than pyrite. Galena was replaced by sphalerite and native telluritim, implying that native tellurittm was the latest mineral in the gold-silver-tellurium system and sphalerite was formed after galena. During the ore-ferming process, the precipitation of pyrite led to the decrease in fS2 of the ore fluids and the subsequent precipitation of galena, chalcopyrite and sphalerite. Under the conditions of medium-low temperature, low fS2 (≤10-15) and low fTc2(≤10-15.6) after the crystallization of pyrite, gold and silver transported in the forms of Au(HS)2-, Au(H2STe)-, Ag(HS)2- and Ag(H2STe)- were precipitated, thus forming native Gold, native silver and gold-sillver tellurides associated with galena and chalcopyrite. The precipitation of gold and silver caused the increase in fTc2 (to≥10-6.7) of the ore fluids and the precipitation of native tellurium.
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崔艳合；亓绍玫；彭明生；史彬.1994.北京市得田沟金矿床矿物特征和金的赋存状态[J].矿床地质,13(3):260~270.1994.Mineral characteristics and modes of occurrence of gold in the Detiangou gold deposit, Beijing[J].Mineral Deposits13(3):260~270
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