本文選題：火山巖成因 + 成礦地質(zhì)背景��； 參考：《成都理工大學》2015年碩士論文

【摘要】：多龍礦集區(qū)鐵格隆南銅(金)礦床的勘查與突破是近年來班公湖-怒江成礦帶內(nèi)取得的最令人矚目的找礦勘查成果,礦床類型的厘定對區(qū)域找礦工作奠定了重要的理論和勘查評價研究基礎,加強對該礦床的成礦地質(zhì)背景研究,無疑對區(qū)域找礦及勘查突破具有重要的指導意義。本文以多龍礦集區(qū)美日切錯組火山巖為研究對象,通過詳細野外地質(zhì)調(diào)查、巖石學、同位素年代學、巖石地球化學及同位素地球化學等研究工作,探討了火山巖成巖與鐵格隆南礦床成礦的關系。LA-ICP-MS鋯石U-Pb年代學研究表明,鐵格隆南礦區(qū)安山巖成巖年齡為(110.01±0.68)Ma(MSWD=2.3),形成于早白堊世。通過對礦區(qū)安山巖頂?shù)捉缑娴臄?shù)學模擬,認為礦區(qū)地表的火山噴發(fā)類型為中心-裂隙組合噴發(fā)。進一步詳細的巖石學及巖石地球化學研究表明,美日切錯組火山巖以發(fā)育一套玄武巖-玄武質(zhì)安山巖-安山巖-英安巖的巖石組合類型,具有由不成熟弧向成熟弧過渡,并向成熟大陸邊緣弧轉(zhuǎn)化的特征。巖石地球化學特征限定其具有島弧火山巖的巖石地球化學特征,巖漿源區(qū)來自于Ⅱ型富集地幔(EMⅡ),是俯沖沉積物熔體交代地幔源區(qū)部分熔融的產(chǎn)物,在巖漿上升過程中混染了上地殼物質(zhì),產(chǎn)出構(gòu)造背景限定于安第斯型活動大陸邊緣,表明其屬一套典型的大陸邊緣型島弧火山巖,形成于早白堊世班公湖-怒江洋盆向北俯沖的動力學背景下,是該動力學背景下誘發(fā)的巖漿產(chǎn)物?鐵格隆南礦區(qū)安山巖包體的巖石學研究表明,其巖性為主要產(chǎn)出于造山環(huán)境的輝石安山巖,產(chǎn)出位置與鐵格隆南礦體的空間位置之間的關系更加緊密。含包體安山巖的分布范圍可能指示了鐵格隆南礦體的分布位置,是該礦區(qū)內(nèi)重要的近礦找礦標志之一。綜上所述,鐵格隆南礦區(qū)美日切錯組火山巖的形成時間應晚于鐵格隆南礦床的形成時間,在礦體形成后發(fā)生侵蝕作用的初期即覆蓋于礦體之上,是該礦床得以完好保存的重要條件之一。同時美日切錯組火山巖的研究為鐵格隆南礦床的成礦地質(zhì)背景研究提供了更多的證據(jù)支持。
[Abstract]:The exploration and breakthrough of the Tiegelongnan copper (gold) deposit in the Dulong ore concentration area is the most remarkable result of prospecting and exploration in recent years in the Bangong Lake-Nujiang metallogenic belt.The determination of ore deposit types has laid an important theoretical foundation for regional prospecting and exploration and evaluation, and strengthening the study of the metallogenic geological background of the deposit is undoubtedly of great significance for regional prospecting and exploration breakthroughs.Based on the detailed field geological survey, petrology, isotopic chronology, geochemistry and isotopic geochemistry, the volcanic rocks of the Meijichijiao formation in the Dulong ore concentration area are studied in this paper.The relationship between volcanic diagenesis and mineralization of Tiegelongnan deposit. LA-ICP-MS zircon U-Pb chronology study shows that the diagenetic age of andesite in Tiegelongnan ore area is about 110.01 鹵0.68 MaMSWDU 2.3, which was formed in early Cretaceous.Through the mathematical simulation of the roof and bottom interface of the andesite in the mining area, it is considered that the type of volcanic eruption on the surface of the mining area is the center-fissure combination eruption.Further detailed petrological and petrogeochemical studies indicate that the volcanic rocks of the Mei-Japan Chijiao formation have developed a set of rock assemblages of basalt, Black Tortoise andesite, andesite andesite andesite, with a transition from immature arc to mature arc.And the characteristics of the arc transformation to the mature continental margin.The petrogeochemical characteristics limit its petrogeochemical characteristics of island arc volcanic rocks. The magma source region is derived from type 鈪，

本文編號：1765361