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巴西地盾的上前寒武系,无论是在地槽褶皱区,还是在地台型的非褶皱区,都可以划分出几个不同时期的构造—物质组合。在巴西地盾上,可能除了,地台外都是在前寒武纪末期开始形成的。米纳斯和伊塔哥尔群以及和他们相类似的岩系形成的组合,是属于上前寒武系形成的最古老的褶皱。该组合的成分、构造及其与岩浆作用的关系、侧向变化规律性等以南部米纳斯—吉拉斯州四角规铁矿研究的比较好。分布在这里的上前寒武系剖面往往被作为标准剖面;因此对它的特征了解的较详细。
The Precambrian system of the Brazilian shield can be divided into several different periods of tectonic-material assemblages, both in the geosyncline fold zone and the platform-type non-fold zone. On the Brazilian shield, it is probable that, except at the platform, the formation began at the end of the Precambrian. The combination of the Minas and Itaquil, and their similar rock series, belongs to the oldest fold formed by the Precambrian system. The combination of composition, structure and its relationship with the magmatism, lateral variation regularity southern Minas Gerais State corner of the iron ore research is better. Precambrian profiles distributed here are often used as standard profiles; therefore, a more detailed understanding of their features is provided.