(1. 中南大學(xué) 有色金屬成礦預(yù)測教育部重點實驗室，長沙 410083；
2. 中南大學(xué) 地球科學(xué)與信息物理學(xué)院，長沙 410083)
摘 要: 三色溝礦區(qū)位于我國著名成礦帶之一的東昆侖造山帶中部，礦區(qū)出現(xiàn)的主要礦化類型包括脈型鉛鋅礦化和斑巖型銅礦化。流體包裹體研究表明，三色溝礦區(qū)流體包裹體類型包括氣液兩相水溶液包裹體(Ⅰ型)、水溶液−CO2包裹體(Ⅱ型)和純CO2包裹體(Ⅲ型)。成礦流體具有低鹽度、低密度的特點，鉛鋅成礦溫度下限值為178~209 ℃，鹽度為0.3%~18.8%(NaCleq)，估算成礦壓力為50~143 MPa；銅礦化成礦溫度下限值為182~228 ℃，鹽度為3.5%~18.8%(NaCleq)，估算成礦壓力為71~164 MPa。成礦過程中流體發(fā)生相分離，對多金屬硫化物的沉淀起到重要作用。結(jié)合礦區(qū)的地質(zhì)演化史，認(rèn)為礦區(qū)中部與巖漿熱液作用有關(guān)的斑巖型銅礦化，與區(qū)內(nèi)強烈發(fā)育的鉛鋅礦化均為同一構(gòu)造−巖漿作用的產(chǎn)物。
關(guān)鍵字: 流體包裹體；成礦流體；東昆侖；三色溝；礦床成因
Sansegou Pb-Zn deposit in Qinghai Province, China
（1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China）
Abstract:The Sansegou Pb-Zn deposit is located in the eastern Kunlun orogenic belt, one of the famous metallogenic belt in China. The main mineralized types in the deposit are vein-type Pb-Zn mineralization and porphyry-style copper mineralization. Fluid inclusion studies indicate that the fluid inclusions are in three types: two-phase aqueous inclusion (typeⅠ), three-phase CO2-aqueous fluid inclusion (type Ⅱ) and pure CO2 fluid inclusion (type Ⅲ). The ore-forming hydrothermal fluids are characterized by low salinity, low density, and the Pb-Zn mineralizing temperatures range from 178 to 209 ℃, low salinities range from 0.3% to 18.8% NaCl equivalent, and the calculated pressure ranges from 50 to 143 MPa; the porphyry copper mineralizing temperatures range from 182 to 228 ℃, salinities range from 3.5% to 18.8% NaCl equivalent, and the calculated pressure ranges from 71 to 164 MPa. The immiscibility of ore-forming fluids plays an important role in the metallogentic process of Pb-Zn-Cu deposit. Associated with the tectonic environment, it is suggested that the porphyry-style copper mineralization in the central part of the ore district which is related to magmatic hydrothermal activities is the result of the same tectionic-magmatic activities as Pb-Zn mineralization.
Key words: fluid inclusions; ore-forming fluid; eastern Kunlun; Sansegou; deposit genesis
