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长坑－ 富湾超大型银矿床主要产在下石炭统灰岩与上三叠统页岩断层不整合面下的硅质岩及灰岩中，矿化多为脉状，主要由石英、方解石、方铅矿、闪锌矿及银矿物组成。成矿流体Ｒｂ－ Ｓｒ 等时线年龄为６８±８．５Ｍａ，表明成矿发生在５９．５—７６．５ Ｍａ 之间。（８７Ｓｒ／８６Ｓｒ）Ｉ＝ ０．７１６４。成矿流体δ１８Ｏ 在－ ０．８６‰—４．１‰之间，δＤ 在－ ３９．８‰—－ ５９‰之间，表明成矿流体为循环大气降水或建造水。银矿床铅同位素组成和产于中新元古代地层中茶洞银矿床方铅矿的铅同位素组成基本一致。据成矿年龄、成矿流体氢氧同位素组成及铅同位素组成特点，认为长坑－ 富湾超大型独立银矿床是晚白垩世至第三纪火山及次火山活动加热循环大气降水及建造水溶解深部矿源岩中经过早期成矿富集的成矿物质，迁移至灰岩与硅质岩及硅质岩与页岩界面时沉淀析出形成的。
The Changkeng-Fuwan super-large silver deposit is mainly produced in cherts and limestones under the unconformity between the Lower Carboniferous limestone and the Upper Triassic shale. The mineralization is mostly vein-shaped and consists mainly of quartz, calcite, Galena, sphalerite and silver minerals. The Rb-Sr isochron age of the ore-forming fluid is 68 ± 8.5 Ma, indicating that mineralization occurred between 59.5-76.5 Ma. (87Sr / 86Sr) I = 0.7164. The δ18O of the ore-forming fluid is between -0.88 ‰ -4.1 ‰ and δD is between -39.8 ‰ and 59 ‰, indicating that the ore-forming fluid is cyclic atmospheric precipitation or water. The lead isotopic composition of the silver deposit and the Pb isotopic composition of galena from the Zhidong silver deposit in the Neoproterozoic strata are basically the same. According to the age of ore-forming, the composition of hydrogen and oxygen isotopes of ore-forming fluids and the composition of lead isotopes, it is concluded that the Chang-Fu-Wan ultra-large-scale independent silver deposit is characterized by the activities of heating and circulation of the Lower Cretaceous to Tertiary volcanic and sub-volcanoes, Early mineralization in the deep source rocks through the early mineralization enrichment of ore-forming material, migrate to the limestone and silicalite and silicalite and shale interface precipitates formed.