为弥补云南省香格里拉伊隆迈勘查区岩石学及地球化学研究的空白,系统总结了该区火山岩的岩石学特征;并结合主量、微量及稀土元素数据及各类投点图,分析探讨火山岩的地球化学特征及其地质意义.结果表明:火山岩SiO2含量为41.91%~47.75%,σ=0.005~27.94,m/f=0.3~1.73,为富铁质-铁质超基性-基性岩,Al2O3含量(13.03%~21.54%)较高,全碱ALK=0.13%~5.48%;岩石Rb、Sr、Th、U等大离子亲石元素相对亏损,Nb、Zr、Ta等高场强元素相对富集,Ti显著富集;火山岩主量、微量元素以及地球化学指标的差异性表明该区存在多期次的火山喷发;火山岩的稀土元素总量∑REE较高,为85.86×10-6~137.58×10-6,稀土元素配分图为平滑的右倾曲线,LREE/HREE为3.16~7.16,(La/Yb)N为3.27~9.66,表现为轻稀土中等富集以及轻重稀土分异不明显.%In order to make up for the gap of petrological and geochemical study of Yilongmai exploration region in Shangri-La, Yunnan province, the petrological characteristics of volcanics of exploration region and combined with the major elements, trace elements, REE and various types of diagram, and explore the geochemical characteristics and its geological significance of volcanics were summarized.The experimental result indicated that the content of SiO2 in volcanics is 41.91~47.75, the Litman index is 0.005~27.94, m/f is 0.3~1.73 show that these are mafic-ultramafic of iron-rich to iron.Al2O3 is 13.03~21.54 and ALK is 0.13~5.48.Rb, Sr, Th, U,etc.lithophile element are relative loss, Nb, Zr, Ta, etc.High field strength elements are relative enrichment, and Ti is significant enrichment in volcanics.The difference of the major elements, trace elements and geochemical indicators shows that there are multi-stage volcanic eruption in the area.∑REE is relatively high, between 85.86×10-6~137.58×10-6,chondrite-normalized REE patterns are smooth right deviation curves.LREE/HREE is between 3.16~7.16,(La/Yb)N is between 3.27~9.66.Light REE is medium enrichment and fractionation of REE is not obvious.
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