本文選題：班公湖—怒江成礦帶 + 東窩東銅礦床��； 參考：《現(xiàn)代地質(zhì)》2016年06期

【摘要】：西藏改則縣東窩東銅多金屬礦床位于西藏多龍礦集區(qū)東部,是近年來班公湖—怒江成礦帶上新發(fā)現(xiàn)的銅多金屬礦。對區(qū)內(nèi)花崗閃長斑巖和花崗斑巖進(jìn)行了LA-ICP-MS鋯石U-Pb年代學(xué)測試顯示,成巖年齡為(121.0±1.2)Ma和(121.5±1.0)Ma,與多龍礦集區(qū)內(nèi)成巖成礦年齡相近。研究區(qū)含礦斑巖顯示了富集輕稀土和大離子親石元素,虧損重稀土和高場強(qiáng)元素,中等Eu負(fù)異常,高鋁、低鎂、低鈦,高Sr、低Y及Yb的島弧巖漿巖特征,暗示礦區(qū)含礦巖漿與多龍礦集區(qū)含礦巖漿具備相同的巖漿源區(qū)。礦區(qū)含礦斑巖的鋯飽和溫度介于779.6~844.5℃,地球化學(xué)數(shù)據(jù)顯示高Sr低Nd及低εNd(t)值特征;含礦斑巖εHf(t)為+3.4~+11.1,兩階段模式年齡T2DMC為467~963 Ma;表明其與多龍礦區(qū)含礦斑巖具備相似的Sr-Nd-Hf同位素特征,暗示了礦區(qū)含礦斑巖是班公湖—怒江特提斯洋洋殼向北俯沖消減背景下,由玄武質(zhì)新生下地殼在較高溫度條件下部分熔融形成的產(chǎn)物,指示班公湖—怒江洋盆于早白堊世晚期尚未關(guān)閉。野外地質(zhì)調(diào)查發(fā)現(xiàn),礦區(qū)發(fā)育典型斑巖銅礦蝕變分帶;具備與多龍礦集區(qū)的巖石組成、礦化及蝕變、成巖成礦時(shí)代、構(gòu)造環(huán)境和物質(zhì)來源相類似的特征,且空間位置相近,暗示兩者受控于統(tǒng)一的構(gòu)造-巖漿成礦系統(tǒng)。綜合分析認(rèn)為,東窩東地區(qū)為多龍礦集區(qū)東延部分,具有尋找斑巖-淺成低溫?zé)嵋盒豌~(金)礦床隱伏礦體的良好潛力。
[Abstract]:The Dongwodong copper polymetallic deposit, located in the eastern part of the Dulong ore concentration area in Tibet, is a newly discovered copper polymetallic deposit in the Bangong Lake-Nujiang metallogenic belt in recent years. The LA-ICP-MS zircon U-Pb geochronology of granodiorite and granodiorite in this area shows that the diagenetic ages are 121.0 鹵1.2)Ma and 121.5 鹵1.0 Ma, which are similar to those in the Dulong ore accumulation area. The ore-bearing porphyry in the study area shows the characteristics of island arc magmatic rocks enriched in light rare earths and large ion lithophile elements, depleted heavy rare earths and high field strength elements, medium EU negative anomalies, high aluminum, low magnesium, low titanium, high Sr, low Y and Yb, It suggests that the ore bearing magma has the same magma source as the ore bearing magma in the Dulong ore concentration area. The zirconium saturation temperature of ore-bearing porphyry is between 779.6 鈩，

本文編號：1813839