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凉城、四子王旗、三义堂和大同的地幔包体的岩石学和矿物的主、微量元素成分显示华北克拉通中、西部北缘总体为过渡型岩石圈地幔,为原始地幔经过不同程度的熔体抽取和后期交代富集作用的残留。凉城岩石圈地幔经历的熔体抽取程度最低,后期交代富集作用比较强烈,这与其橄榄岩中尖晶石的Cr#较低,并且共存的单斜辉石的Mg#较低一致。三义堂岩石圈地幔经历的熔体抽取程度最高,后期交代富集作用最强烈,不同样品甚至同一样品中不同单斜辉石颗粒的La/Yb和LREE配分模式变化范围非常大,且矿物边部比核部更富集微量元素。大同、四子王旗岩石圈地幔经历的熔体抽取程度介于凉城和三义堂之间,但后期的交代富集作用明显不如凉城和三义堂强烈。研究区的岩石圈地幔主要受硅酸盐熔体交代作用的影响,只有三义堂岩石圈地幔还可能也受到了碳酸盐交代作用的影响。
The lithology and major and trace element compositions of the Liangcheng, Siziwangqi, Sanyi and Datong mantle inclusions show that the central and western parts of North China Craton are generally transitional lithospheric mantle, and the original mantle undergoes different degrees of melting Volume extraction and later explain the role of enrichment residues. The Liangcheng lithospheric mantle experienced the lowest degree of melt extraction and had a relatively strong post-stage enrichment effect, which was lower than the Cr # of spinel in peridotite and the lower Mg # of coexisting clinopyroxenes. The Sanyitang lithospheric mantle experienced the highest degree of melt extraction and the later stage had the highest degree of enrichment. The La / Yb and LREE partition modes of different clinopyroxene particles in different samples and even in the same sample varied greatly, Department of nuclear enrichment of more than trace elements. Datong, Siziwangqi lithospheric mantle experiencing the melting degree between the range of Liangcheng and Sanyi Church, but the late account of enrichment was significantly less than Liangcheng and Sanyi Church strong. The lithospheric mantle in the study area is mainly affected by the silicate melt metasomatism. Only the lithospheric mantle of the Sanyi Tang area may also be affected by carbonate metasomatism.