發(fā)布時間：2018-06-14 15:01

  本文選題：LA-ICP-MS鋯石U-Pb測年 + 黑云二長花崗巖��； 參考：《地質(zhì)通報》2017年06期

【摘要】：虎頭崖鉛鋅多金屬礦床位于東昆侖祁漫塔格地區(qū),礦區(qū)內(nèi)中酸性侵入巖體廣泛發(fā)育,且與成礦關(guān)系密切。通過高精度LA-ICP-MS鋯石微區(qū)原位U-Pb同位素測年,獲得與礦化、矽卡巖化關(guān)系密切的黑云二長花崗巖鋯石的~(206)Pb/~(238)U年齡加權(quán)平均值為234.2±1.5Ma。地球化學(xué)分析表明,黑云二長花崗巖具有高Al_2O_3、K_2O,低TiO_2、Na_2O的特征,稀土和微量元素顯示其富集輕稀土元素、Rb、Th和部分高場強元素,Nb、Sr、Zr相對虧損,稀土元素表現(xiàn)為LREE/HREE明顯分離的配分模式,總體表現(xiàn)為I型花崗巖的特征。在(Y+Nb)-Rb圖解中落入后碰撞花崗巖區(qū),在R1-R2因子判別圖上落入造山晚期和同碰撞花崗巖重疊區(qū),顯示其可能形成于碰撞-后碰撞構(gòu)造階段�；㈩^崖鉛鋅多金屬礦區(qū)Ⅵ礦帶具有強烈的矽卡巖化,結(jié)合礦石組構(gòu)、脈石礦物、圍巖蝕變等特征,認(rèn)為其具有矽卡巖型礦床的特征,形成于234.2±1.5Ma(中—晚三疊世)。
[Abstract]:The Hutouya Pb-Zn polymetallic deposit is located in the Qimantage area of East Kunlun Mountains. The intermediate-acid intrusive rocks are widely developed in the ore area and are closely related to mineralization. Based on the in situ U-Pb isotopic dating in the LA-ICP-MS zircon microregion, a weighted average of 234.2 鹵1.5 Ma for zircon zircons from the black cloud monzonitic granite, closely related to mineralization and skarn mineralization, is obtained, and the weighted average age of zircon is 234.2 鹵1.5 Ma.The zircon of the La-ICP-MS zircon is closely related to mineralization and skarn mineralization. Geochemical analysis shows that the bifeldite has the characteristics of high Al2O3K _ 2O and low TiO-2 ~ + Na _ 2O. Rare earth and trace elements show relative depletion in the enrichment of light rare earth elements (RbTh) and some high-field strength elements (Nb-Sr-Zr), and the REE is characterized by an obvious separation pattern of LREE / hree. It is characterized by I type granite in general. It falls into the post-collision granite area in the Y Nb-Rb diagram, and falls into the late orogenic and syncollisional granite overlapping areas on the R1-R2 factor discriminant diagram, indicating that it may have been formed in the collision-post-collision tectonic stage. The 鈪，

本文編號：2017790