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在晋、冀、蒙交界处的高级变质岩区，沿孔兹岩系和怀安麻粒岩杂岩的接触带上广泛发育石榴石基性麻粒岩，其主要特征：1）以透镜状、岩脉状分布于孔兹岩系和麻粒岩杂岩的接触带上；2）和孔兹岩系及麻粒岩杂岩的接触关系为侵入或韧性剪切接触；3）具斜方辉石－单斜辉石－角闪石－斜长石－石榴石的矿物组合及围绕石榴石发育斜长石和角闪石或斜方辉石的交生结构，部分还可见到斜方辉石后成合晶定向排列；4）在孔兹岩和麻粒岩的接触带上还有透镜状的角闪辉石岩、脉状的斜长岩；5）具等温降压的PT轨迹，并有200－300MPa的压力降，具有陆-陆碰撞的特征；6）同位素年龄资料显示，岩石的定位年龄约为1800Ma。因此，石榴石基性麻粒岩是下地壳深源岩浆在吕梁运动时沿不同地体的对接带上侵的深源侵入体，并和孔兹岩岩片、（超）基性岩体一同构成复杂的具混杂岩性质的构造岩浆杂岩带，其出现部位能指明不同地体的对接部位。
In the advanced metamorphic rock area at the junction of Shanxi, Hebei and Mongolia, garnet-based granulite is widely developed on the contact zones of the Khondzian and Huai’an granulite complexes. The main features are: 1) , And the veins are distributed on the contact zones of the khondalite and granulite complexes; 2) the contact with the khondalite and granulite complexes is intrusive or ductile shear contact; 3) Pyroxene-clinopyroxene-amphibole-plagioclase-garnet mineral assemblages and the phylogenetic structure of plagioclase and hornblende or orthopyroxenes around garnet, and some of them also show orthopyroxene And then crystallized; 4) there are lenticular pyroxene and vein-like plagioclase on the contact zone of khodal and granulite; 5) PT trajectory with isothermal depressurization and 200-300MPa pressure drop, with land-continent collision characteristics; 6) isotope age data show that the positioning of the rock age of about 1800Ma. Therefore, the garnet-based granulite is a deep-sourced intrusive body intruded along the buttress belt of different terranes during the movement of the deep source magma in the lower crust and formed with the khondalite and (super) basic rock mass The complicated melange magmatic complex with melange features its appearing parts that can indicate the connecting parts of different terrains.