本文選題：花崗閃長巖 + 鋯石U-Pb年齡��； 參考：《地質(zhì)論評(píng)》2017年02期

【摘要】：塔吉里霞隆花崗閃長巖體位于岡底斯構(gòu)造巖漿巖帶西段,拉薩地塊中西部。巖石w(SiO_2)=63.38%~72.56%;w(Al_2O_3)=13.85%~15.73%;Alk(K_2O+Na_2O)=5.12%~6.79%;w(K_2O)/w(Na_2O)=0.67~1.32;A/CNK=0.90~1.02,屬Ⅰ型弱過鋁質(zhì)高鉀鈣堿性系列。稀土總量∑REE=128.34×10~(-6)~167.25×10~(-6),LREE/HREE=6.94~10.73,輕稀土富集重稀土虧損,配分曲線呈右傾型;δEu=0.69~0.86,弱負(fù)銪異常。巖石具有富集Rb、Th、K等大離子親石元素,而虧損Ba、U、Nb、P等高場強(qiáng)元素的特征,巖石顯示出島弧火山巖親緣性。鋯石U@b定年結(jié)果表明,塔吉里霞隆巖體主要侵位于126.3±1.1Ma,屬早白堊世晚期。塔吉里霞隆花崗閃長巖顯示出殼�；旌显刺卣�,班公湖-怒江洋殼巖石圈的南向俯沖和隨后發(fā)生的板片回轉(zhuǎn)可以較好的解釋巖體成因。
[Abstract]:The granodiorite is located in the western section of the Gangdis tectonic magmatic belt and in the west-west of Lhasa block.The number of rocks wsio _ 2 ~ + 63.38 is 72.56 / W / S / W / S / T 13.85 / 15.73T / K / K _ 2O / K _ 2O / Na2OT = 5.1212 / 6.79A / W / S / K _ 2O / K _ 2O / S / P 0.67A / CNK 0.90 / 1.02a, belonging to the type I series of weak peraluminous high-potassium calc-alkaline series.The total amount of rare earth is 鈭，

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