發(fā)布時間：2018-04-18 19:50

  本文選題：燕山期花崗巖 + 源區(qū)��； 參考：《中南大學(xué)學(xué)報(自然科學(xué)版)》2017年01期

【摘要】：對湖南茶陵錫田和鄧阜仙復(fù)式巖體燕山期二云母花崗巖進行巖相學(xué)、鋯石及巖石元素地球化學(xué)特征的對比研究,以探討其源區(qū)可能的差異對鎢錫多金屬成礦的影響。研究結(jié)果表明:錫田與鄧阜仙二云母花崗巖均顯示為高硅、高鋁、富堿特征,較高的10 000w(Ga)/w(Al)(分別為3.58~4.20和2.04~4.11,w為質(zhì)量分?jǐn)?shù))指示其為A型花崗巖;w(Nd)/w(Th)15和w(Th)/w(U)1特征指示兩者為殼源,但錫田巖體較鄧阜仙巖體含磷低,更富稀土元素,其Eu負(fù)異常(δ(Eu)=0.03~0.04)較鄧阜仙巖體(δ(Eu)=0.24~0.85)更顯著,輕重稀土分餾程度更低,其稀土配分曲線呈"對稱"型,而鄧阜仙巖體為"右傾"型;由鋯石組分計算的錫田與鄧阜仙巖漿結(jié)晶溫度分別為823~945℃和613~922℃,氧逸度lg(fo_2/10~5 Pa)分別為-14.7和-16.8,表明兩巖體均為形成伸展背景下的A型花崗巖,是元古宙地殼部分熔融產(chǎn)物;源區(qū)以碎屑巖為主,錫田巖體源區(qū)應(yīng)更富火成巖,這表明同為殼源,且同期、空間相鄰巖體仍可存在源區(qū)和成巖環(huán)境的差異,這種物源背景差異對成礦產(chǎn)生影響。
[Abstract]:The petrographic, zircon and element geochemical characteristics of the Yanshanian metamorphic granites of the Chaling Xitian and Dengfu Xianshen complex intrusions were studied in order to explore the influence of the possible source regions on the mineralization of tungsten and tin polymetallic deposits.The results show that both Xitian and Dengfu Xiandimica granites are characterized by high silicon, high aluminum and rich alkali. The higher 10000w / w Gaan / w / w (3.58 ~ 4.20 and 2.044 ~ 4.11w mass fractions respectively) indicate that they are A-type granitoids and w(Th)/w(U)1 characteristics indicate that they are crusts, and the characteristics of w(Th)/w(U)1 indicate that they are crust source, and the results show that the two types of granites are high in silicon, high in aluminum and rich in alkali-rich elements.However, the Xitian rock body has lower phosphorus content and more rare earth elements than the Dengfuxian rock mass. The EU negative anomaly (未 ~ (2 +) EU (0.03) 0.04) is more significant than that of the Dengfu Xianshan rock mass (未 ~ (2 +) EU ~ (2 +) 0.240.85), and the fractionation degree of heavy and heavy rare earth elements is lower, and the REE distribution curve is "symmetrical" type, while the "right dip" type of the Dengfu Xianshan rock mass.The crystallization temperatures of Xitian magma and Dengfuxian magma calculated from zircon composition are 823 ~ 945 鈩，

本文編號：1769820