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燕辽－阴山地区 １５个碱性岩体同位素年龄的变化范围为 １９０～２６８ Ｍａ，其中 １０ 个年龄在 ２０８～２５０ Ｍａ之间，指示出它们主要形成于三叠纪． ε_（Ｎｄ）（ｔ），ε_（Ｓｒ）（ｔ）和Ｉｓｒ（ｔ）初始值 变化范围分别为－３．２１～１７．１９， １１．７～７１．５和 ０．７０５ ０～０．７０９ ３，平均值依次是－７．０９， ３６．６３和 ０．７０６ ８，反映出它们的富集性质．在ε_（Ｎｄ）（ｔ）－ ε_（Ｓｒ）（ｔ）相关图中，这些岩石的投影点 均落在富集地幔演化趋势线内及其附近，并具有地幔铅的同位素组成，表明它们与富 集地幔储库物质关系密切．
The isotopic ages of the 15 alkaline rocks in the Yanliao-Yinshan area ranged from 190 to 268 Ma, of which 10 were between 208 and 250 Ma, indicating that they were mainly formed in the Triassic. The initial values of ε Nd, t Sr, and Isr t vary from -3.21 to 17.19, from 11.7 to 71.5 and from 0.705 0 to 0, respectively. 709 3, followed by the average -7.09, 36.63 and 0.706 8, reflecting their enrichment properties. The projection points of these rocks all fall within and near the trend line of enrichment of mantle in the Nd (t) - ε Sr (t) correlation diagram and have the isotopic composition of mantle lead, indicating that they are related to Rich mantle reservoir matter is closely related.