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华北克拉通不同时代基性火山岩存在向富集方向演化的趋势，并出现明显的Ａｒ－Ｐｔ界限和新生代异常．元古宙基性火山岩比太古宙富集大部分高场强元素（ＨＦＳＥ）和轻稀土元素（ＬＲＥＥ），ＲＥＥ分异程度显著增加，而且相容性接近的不相容元素（如Ｎｂ，Ｔａ）的相对不相容性发生了改变．新生代玄武岩ＨＦＳＥ及Ｎｉ高度富集，ＲＥＥ强烈分异，δ（Ｅｕ）值最高．Ａｒ－Ｐｔ界限可能与地幔熔融时物理条件（如氧逸度）的改变和地幔富集作用有关．新生代玄武岩独特的地球化学特征可能主要反映了地幔源区的特殊性———“似ＯＩＢ型”富集地幔，其形成既可能有携带远洋沉积物的俯冲古老玄武岩洋壳部分熔融残余的贡献，也可能有直接循环（如通过拆沉作用）的陆壳物质的贡献，同时还可能涉及了地幔柱活动的影响．
The basic volcanic rocks of different ages in North China Craton have evolved toward the enrichment direction with obvious Ar-Pt boundary and Cenozoic anomalies. The Paleozoic basic volcanic rocks enriched most of the HFSE and LREE than the Archean, with a significant increase in the REE degree of differentiation and the incompatible elements with similar compatibility such as Nb, Ta ) Has changed its relative incompatibility. The HFSE and Ni in the Cenozoic basalts were highly enriched, with strong REE and highest δ (Eu) values. The Ar-Pt boundary may be related to changes in physical conditions (such as oxygen fugacity) and mantle enrichment during mantle melting. The unique geochemical characteristics of the Cenozoic basalts may mainly reflect the particularity of the mantle source area - “OIB-like” enrichment of the mantle, which contributes to the contribution of partial melting remnants of the subducted ancient basalt oceanic crust that may carry the oceanic sediments , Or the contribution of continental crust material that has been directly recycled (such as through delamination), but may have implications for mantle plume activity.