2. Explanation the formation conditions and processes of epithermal ore deposit by reading the following model figure. VOLCANIC-HYDROTHERMAL SYSTEM GEOTHERMAL SYSTEM 50°900 6O>, HCL, CO? Crater lake y20030 Hotsprings CO,,, S COn, I ICL. S :" Acidic fluid Low sulfidation 200 High Sulfidation Ag 300° Au, Cu Porphyry Cu(Mo, Au) Far Saline magmatic fluld Liquid flow por ascent Approximate Fig. lI Schemane cross-section showing shallow suh-volcanic intrus ons and associaed stratovolcano, and environments deduced tor formation of porphyry Cu, ard high- and low- degassing ma2u021Aw山 IRI sstes extend fru sulfiua is n epithet mal ue les und acidic spines, and incorporate porphyry and or high sulfide:icn ore env ronments. whereas low-sulfidation re depsits form fror geothermal systems characterized by ncutrul-pH waters tha: may discharge as bot springs. Low sulfide deposits high sulfide deposits Disseminated ore dominant, replacement Open-space veins dominant, stockwork ore ore common Disseminated and replacement ore minor ◆ Textures Stockwork ore minor, veins commonly Veins, cavity filling (bands, colloform, subordinate druses), breccias Wallrock replacement, breccias, veins ◆ Ore minerals Pyrite, electrum, gold, sphalerite, galena Pyrite, enargite, chalcopyrite, tennanite, (asrenopyrite) covellite, gold, tellurides ◆ Gangue alunite, barite kaolinite Quartz, chalcedony, calcite, adularia, illite, pryophyllite carbonates ◆ Metals Au, Ag, zn, pb(cu, sb, a Cu, Au, Ag, As(Pb, Hg sb, Te, sn, Mo, bi)2. Explanation the formation conditions and processes of epithermol ore deposit by reading the following model figure. Answer: Low sulfide deposits high sulfide deposits Deposit Form Open-space veins dominant, stockwork ore common Disseminated and replacement ore minor ◈ Textures Veins, cavity filling (bands, colloforms, druses), breccias ◈ Ore Minerals Pyrite, electrum, gold, sphalerite, galena (asrenopyrite) ◈ Gangue Quartz, chalcedony, calcite, adularia, illite, carbonates ◈ Metals Disseminated ore dominant, replacement ore common Stockwork ore minor, veins commonly subordinate Wallrock replacement, breccias, veins Pyrite, enargite, chalcopyrite, tennanite, covellite, gold, tellurides Quartz, alunite, barite, kaolinite, pryophyllite •Au, Ag, Zn, Pb (Cu, Sb, As Cu, Au, Ag, As (Pb, Hg, Sb, Te, Sn, Mo, Bi)