本文選題：紅山Cu礦床 + 流體包裹體��； 參考：《中國地質(zhì)大學(xué)(北京)》2015年碩士論文

【摘要】：紅山Cu礦床是義敦島弧南段已探明規(guī)模最大的斑巖-矽卡巖型礦床,然迄今對其礦床成因的認識模糊不清,這在一定程度上制約了對紅山Cu礦床形成原因和礦化富集規(guī)律的認識。為此,論文在礦床地質(zhì)研究的基礎(chǔ)上,通過巖相學(xué)觀察,厘定了成礦階段,開展了流體包裹體類型、顯微測溫和C-H-O同位素測試分析,據(jù)此探討了成礦流體的來源、演化與礦床成因機制。1、探明主礦體屬矽卡巖型,其成礦作用過程可劃分為矽卡巖期和石英-硫化物期;前者包括早期矽卡巖、晚期矽卡巖兩個階段,后者包括早期硫化物、晚期硫化物兩個階段。2、流體包裹體主要分為四類:氣液兩相(VL)、富氣相(LV)、含Na Cl子礦物三相(SL)和含CO2三相(LC)。早期矽卡巖階段,包裹體主要為VL、LV、SL、LC型,大多數(shù)為為LV型;晚期矽卡巖階段,包裹體主要為VL型;早期硫化物階段,包裹體類型有VL、LV、SL、LC型;晚期硫化物階段,包裹體主要類型為VL型。3、成礦流體在各階段的均一溫度為:早期矽卡巖階段402.1~529.9℃,晚期矽卡巖階段187.1~450.1℃,早期硫化物階段201.4~451.2℃,晚期硫化物階段163.5~293.5℃。在石英-硫化物期,不同包裹體類型共存、氣液比變化大、均一溫度近似,說明在有沸騰作用發(fā)生。4、氫氧同位素組成顯示成礦流體的來源為:斑晶石英中同位素數(shù)據(jù)研究顯示成礦熱液以巖漿水為主;在早期矽卡巖階段和晚期矽卡巖階段,巖漿熱液與大理巖之間發(fā)生水巖反應(yīng);而在石英-硫化物期,巖漿水與大氣降水混合。5、成礦流體的均一溫度、鹽度在各成礦階段逐漸降低,且在相鄰的成礦階段發(fā)生重合,表明流體演化的連續(xù)性。其形成和演化經(jīng)歷過程可能為:減壓沸騰、巖漿熱液、揮發(fā)分與碳酸鹽巖接觸交代、流體混合作用。紅山Cu礦床主要的金屬富集沉淀機制為流體的沸騰作用。
[Abstract]:The Hongshan Cu deposit is the largest proven porphyry skarn type deposit in the southern segment of Yidun Island Arc. To some extent, it restricts the understanding of the formation reason and mineralization enrichment law of Hongshan Cu deposit. Therefore, on the basis of the geological study of the deposit, the metallogenic stage is determined by petrographic observation, the types of fluid inclusions, microthermometry and C-H-O isotopic analysis are carried out, and the source of the ore-forming fluids is discussed. The mechanism of evolution and genesis of the deposit shows that the main orebody belongs to skarn type and its metallogenic process can be divided into skarn period and quartz-sulfide stage, the former includes two stages: early skarn, late skarn, and early sulfide. The fluid inclusions are mainly classified into four types: gas-liquid two-phase VLA, gas-rich gas phase CO2, NACl-containing mineral three-phase (SLL) and CO2 three-phase (LCV), which are mainly classified into four types of late sulfides in two stages, that is, gas-liquid two-phase (VLV). In the early skarn stage, the inclusions mainly belong to the type of VLT LVS SLN LC, mostly LV type, in the late skarn stage, the inclusions are mainly of the VL type, in the early stage of sulphide, the types of the inclusions are the type of VLL LVS SLC, the late stage of sulphide, and the type of the late stage of sulphide. The main types of inclusions are VL type. 3. The homogenization temperature of ore-forming fluid in each stage is 402.1U 529.9 鈩，

本文編號：1808933