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通过对山西吕梁山东西两侧的界河口和西榆皮地区变基性火山岩的系统采样和测试分析, 其常量、微量、稀土元素地球化学的特征表明该区的变基性火山岩形成于类似现代大陆裂谷的构造环境中. Sm-Nd, Rb-Sr同位素年代学的研究表明, 界河口群变基性火山岩形成于2600 Ma的壳幔分异事件中, 在新太古晚期(2500 Ma±)遭受了麻粒岩相变质作用的改造, 使岩石的Sm-Nd体系发生了重设. 而在古元古代晚期(1800 Ma±)由于吕梁运动的影响, 使岩石的Rb-Sr体系又一次发生变化, 因其强度较小而未涉及Sm-Nd体系. 该区所获得的1600 Ma±的年龄值, 可能与克拉通内局部的岩浆活动有关. 研究结果不支持吕梁群生成于太古代的观点, 而应该是古元古代时期的产物.
Through the systematic sampling and test analysis of the metamorphic volcanic rocks in both Boundary and West Yupi areas on the east and west sides of Lüliang Mountain in Shanxi Province, the characteristics of their constants, trace elements and REE geochemistry show that the metamorphic volcanic rocks in this area are formed in similar modern In the tectonic setting of the continental rift, studies of Sm-Nd and Rb-Sr isotopes indicate that the delocalite volcanic rocks in the Jiaohekou Formation formed during the 2600 Ma crust-mantle divergence event and occurred in the late Neo-Swire (2500 Ma ±) Suffered from the metamorphism of granulite metamorphism, so that the rock of the Sm-Nd system has been reset.And in the late Paleoproterozoic (1800 Ma ±) due to the impact of Lv Liang, the rock Rb-Sr system occurs again , The Sm-Nd system is not involved due to its low intensity, and the age value of 1,600 Ma ± obtained in this area may be related to the local magmatic activity in the craton. The results do not support the view that the Lvliang Group was formed in the Archean , But should be the product of the ancient period of ancient times.