(1. 中南大學 有色金屬成礦預測教育部重點實驗室,長沙 410083;
2. 中南大學 地球科學與信息物理學院,長沙 410083)
摘 要: 踏王山金礦位于海南省戈枕金礦帶東南部,礦體主要產于東西向構造蝕變帶中,礦石類型為蝕變巖型和石英脈型。在詳細的野外地質調查基礎上,對踏王山金礦床流體包裹體特征進行研究,并結合礦體產出形態(tài)特征,對流體來源以及礦床成因進行探討。結果表明:礦區(qū)流體包裹體主要為氣液兩相包裹體和純CO2包裹體,成礦流體具有中低溫(均一溫度為192~362 ℃)、中鹽度(平均值為7.52%)及低密度(0.46~0.87g/cm3)的特征,成礦深度為中深環(huán)境。從包裹體成分上看,流體包裹體既有巖漿水特征(高H2O、H2含量,w(F-)/w(Cl-)≥1),又具有地下熱鹵水的特征(w(Na+)/w(K+)>1),明顯富集Ca2+或者Ca2+含量較高的成分,顯示可能為混合流體。礦床成因為巖漿熱液與地下熱鹵水疊加的復合型中低溫熱液礦床。
關鍵字: 流體包裹體;礦床成因;金礦;海南
(1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Central South University, Changsha 410083, China;
2. School of Geoscience and Info-Physics, Central South University, Changsha 410083, China)
Abstract:The Tawangshan gold deposit is located in the southeast of Gezhen gold ore belt in Hainan Province. The orebody is hosted by east-west tectonic alteration zone. The main mineralized types are altered rock type and quartz vein type. Based on the detailed field geological survey, the characteristics of fluid inclusions were studied, and the origin of ore-forming fluid and deposit genesis were discussed. The results indicate that, in Tawangshan mine area, the fluid inclusions are gas-liquid two-phase type and pure CO2 type, and the characteristics of moderate or low temperature (in homogeneous temperature range of 192-362 ℃), moderate salinities(average of 7.52%), low density (0.46-0.87 g/cm3) and moderate-deep metallogenic depth environment. The composition of fluid inclusions of Tawangshan gold deposit shows that the fluid inclusions have characteristics of both magmatic water (high H2O, H2 content, w(F-)/w(Cl-)≥1) and geothermal brine water (w(Na+)/w(K+)>1), which represents mixing of magmatic water and geothermal brine water, obviously rich in Ca2+ or component with high Ca2+ content. The genesis of Tawangshan gold deposit belongs to the moderate to low temperature hydrothermal deposit complexing with magmatic water and geothermal brine water.
Key words: fluid inclusions; deposit genesis; Au deposit; Hainan


