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文中提供了甘肃西秦岭新生代碱性火山岩全岩稀土、微量元素和Ｓｒ，Ｎｄ同位素分析资料。研究表明，区内火山岩为一种过渡类型岩石，火山岩强烈富集ＬＲＥＥ和亲石元素的特征，以及高的Ｔｉ含量和较高的Ｃｒ，Ｎｉ，Ｃｏ含量，既不同于中国东部新生代玄武岩，也不同于中国西部造山带钾玄岩类火山岩，而显示与洋岛玄武岩和克拉通内某些高钾火山岩相似的地球化学特征。该区火山岩具有较低的ε（Ｎｄ）值和Ｎ（８７Ｓｒ）／Ｎ（８６Ｓｒ）比值，在ｗ（Ｒｂ）／ｗ（Ｎｂ）ｗ（Ｌａ）／ｗ（Ｎｂ），ｗ（Ｂａ）／ｗ（Ｎｂ）ｗ（Ｌａ）／ｗ（Ｎｂ）和ε（Ｎｄ）ｗ（Ｂａ）／ｗ（Ｎｂ）等地球化学判别图中，显示出火山岩源区具有Ｄｕｐａｌ同位素异常和ＥＭⅠ地幔地球化学端员组成，软流圈对火山岩的起源和成因具有重要的贡献，火山岩的地球化学特征指示源区包含了古老大陆下被交代的岩石圈地幔的信息。
In this paper, we provide the data of rare earth elements, trace elements and Sr and Nd isotopic compositions of the Cenozoic alkaline volcanic rocks in western Qinling, Gansu Province. The study shows that volcanic rocks in the area are transitional type rocks. Volcanic rocks strongly enrich the characteristics of LREE and lithophile elements, as well as high Ti content and high contents of Cr, Ni and Co, which are different from those of the Cenozoic basalts in eastern China Is different from the Potash-hosted volcanic rocks in the western orogenic belt of western China and shows similar geochemical characteristics to some high-k volcanic rocks in the Oceanic basalts and the craton. The volcanic rocks in this area have lower values of ε (Nd) and N (87Sr) / N (86Sr) The geochemical discrimination maps of w (Nb) w (La) / w (Nb) and ε (Nd) w (Ba) / w (Nb) show that the volcanic source area has Dupal isotopic anomaly and EMⅠ mantle geochemistry The asthenospheric assemblages and asthenosphere have an important contribution to the origin and cause of volcanic rocks. The geochemical characteristics of volcanic rocks indicate that the source area contains the information of the lithospheric mantle under the ancient continent.