本文選題：鉛鋅銀礦床 + 方解石��； 參考：《地球化學》2016年02期

【摘要】：三道溝鉛鋅銀礦床位于華北陸塊南緣欒川多金屬礦集區(qū)西部。受斷裂控制的薄脈狀礦體賦存于新元古界欒川群南泥湖組碎屑巖、碳酸鹽巖地層中。本文在礦床地質(zhì)特征和礦物學研究的基礎(chǔ)上,對早、中、晚3個成礦階段的9件熱液方解石進行微量元素、稀土元素和Sm-Nd同位素測年研究。結(jié)果表明方解石的稀土元素總量(?REE)為6.42~216μg/g,富集重稀土元素,HREE/LREE比值為1.47~5.94;δEu=0.62~2.71,具弱Ce異常;強烈虧損Nb和Zr,富集Pb。從成礦早階段到晚階段,∑REE值、LREE/HREE比值和δEu值逐漸減小。Y/Ho-La/Ho圖解和Tb/Ca-Tb/La圖解均指示該礦床方解石為熱液成因。方解石147Sm/144Nd和143Nd/144Nd同位素比值具有良好的線性關(guān)系,等時線年齡為(138.3±2.6)Ma(2σ,MSWD=2.3)。結(jié)合礦集區(qū)內(nèi)成巖-成礦年代學資料,認為三道溝礦床與區(qū)內(nèi)最晚階段的花崗質(zhì)巖漿活動(136~142 Ma)有關(guān),屬于欒川Mo-W-Pb-Zn-Ag多金屬成礦系統(tǒng)中的熱液脈型鉛鋅銀礦床。
[Abstract]:Sandaogou lead-zinc-silver deposit is located in the west of Luanchuan polymetallic deposit area in the southern margin of North China continental block. The thin vein orebodies controlled by faults occur in the clastic and carbonate strata of the Nannihu formation of the Luanchuan Group in the Neoproterozoic. Based on the study of geological characteristics and mineralogy of the deposit, the trace elements, rare earth elements and Sm-Nd isotopic dating of 9 hydrothermal calcite in early, middle and late metallogenic stages have been studied in this paper. The results show that the total REE of calcite is 6.42 渭 g / g, the HREE / LREE ratio of enriched heavy rare earth elements is 1.470.94, 未 Eu0.62 / 2.71 is weak ce anomaly, NB and Zrare depleted strongly and PBB is enriched. From the early metallogenic stage to the late stage, the 鈭，

本文編號：1931458