本文選題：流體包裹體 + H-O同位素��； 參考：《中國(guó)地質(zhì)大學(xué)(北京)》2015年碩士論文

【摘要】：岡底斯是我國(guó)重要的斑巖型銅礦帶,東段已發(fā)現(xiàn)一系列大型-超大型斑巖礦床且研究程度較高,而西段僅發(fā)現(xiàn)朱諾一例大型斑巖銅礦床,且研究程度較低,這不利于岡底斯東西段的對(duì)比研究。本文對(duì)朱諾礦床進(jìn)行了流體包裹體巖相學(xué)研究、包裹體測(cè)溫及激光拉曼光譜分析,并與岡底斯東段的驅(qū)龍斑巖礦床開(kāi)展了對(duì)比。研究表明朱諾礦床共發(fā)育四種類(lèi)型包裹體,分別為富液相氣液兩相水溶液包裹體(LV)、富氣相氣液兩相水溶液包裹體(VL)、含子晶多相(LVH)及富CO2三相(C)包裹體。從成礦早期到晚期(即由A脈向B脈至D脈階段),包裹體均一溫度集中分布在350-550℃、250-350℃、250-300℃,鹽度為5%-55%NaCleqv、5%-40%NaCleqv、2%-10%NaCleqv,顯示包裹體均一溫度及鹽度呈遞減趨勢(shì)。而在B脈階段,在顯微鏡下同一視域內(nèi)可見(jiàn)不同類(lèi)型(LV、VL、LVH)的包裹體共存,并且具有相似的均一溫度而鹽度變化較大特征,這是流體沸騰的明顯標(biāo)志,預(yù)示壓力的降低及硫化物的沉淀。通過(guò)壓力估算得到朱諾礦床A、B、D脈階段的成礦深度分別為2.9km、2.7 km、2.3 km。朱諾H-O同位素顯示出明顯的δ18O和δD虧損,這可能是水巖反應(yīng)、巖漿去氣和大氣降水混入共同作用的結(jié)果。通過(guò)與驅(qū)龍銅礦的對(duì)比,朱諾礦床硬石膏發(fā)育相對(duì)較弱,預(yù)示成礦流體氧逸度相對(duì)驅(qū)龍礦床低,此外二者在包裹體類(lèi)型、溫度、鹽度等方面相似,但朱諾的成礦深度比驅(qū)龍的略淺,這在岡底斯西段總體剝蝕程度相對(duì)東段低的背景下是利于礦床的尋找。
[Abstract]:Gangdis is an important porphyry copper deposit in China. A series of large and super-large porphyry deposits have been found in the eastern part of China, and the study is relatively high, while only one large porphyry copper deposit has been discovered in the western section, and the degree of study is relatively low. This is not conducive to the comparative study of the east and west sections of Gundis. In this paper, the petrography of fluid inclusions, the temperature measurement of inclusions and the laser Raman spectroscopy of Juno ore deposits are studied and compared with those of the porphyry deposits in the eastern section of Gangdis. The results show that there are four types of inclusions in Juno deposit. They are liquid-rich gas-liquid two-phase aqueous inclusions, gas-rich gas-liquid two-phase aqueous solution inclusions, CO2 rich gas-liquid two-phase aqueous inclusions, sub-crystalline multiphase inclusions and CO2 rich three-phase aqueous inclusions. From the early metallogenic stage to the late stage (from vein A to vein B to vein D), the homogenization temperature of inclusions is concentrated in 350-550 鈩，

本文編號(hào)：1935470