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河南中部箕山早元古宙安沟群,从岩石组合、地球化学和变形变质作用诸方面具有绿岩带特征。但这一绿岩带不同于太古宙花岗—绿岩地体,其中缺少超镁铁质火山岩,花岗岩极少见,镁铁质火山岩具大陆拉班玄武岩性质,变形程度远不及太古宙绿岩带,是一内硅铝成因的“废弃绿岩带”。综合安沟群绿岩带自身特征、其发育的基底地壳性质以及区域地质资料,说明安沟群绿岩带属于华北地块南部晚太古宙克拉通基底之上的裂谷产物。该裂谷由蚌埠—箕山—崤山—绛县直至五台,是一支位于秦岭海槽北侧开裂未曾成功的陆内裂谷。它与秦岭海槽共同构成的裂谷系,反映了早元古宙华北地块南部的大陆构造破坏作用。
The Early Proterozoic An-gou Group in Jishan, central Henan, has greenstone features from the aspects of rock assemblage, geochemistry and metamorphism and metamorphism. However, this greenstone zone is different from the Archean granite-greenstone, lacking ultramafic volcanics, rare granite, and mafic volcanics with continental Laban Basalt characteristics that are far less deformed than the Archean greenstone belt , Is a cause of silicon-aluminum “abandoned greenstone belt.” Based on the characteristics of the Anlao Group greenstone belts, their underlying crustal properties and regional geological data, it shows that the Anluolou green belt belongs to the rift product of the Late Archean Craton in the southern part of North China. The rift, from Bengbu-Keishan-Dangshan-Jiangxian up to Wutai, is an inland rift that has not been successfully cracked on the northern side of Qinling Trough. The rift system formed by it together with the Qinling Trough reflects the tectonic disruption of the continental structure in the southern part of North China in Early Proterozoic.