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绿岩带是主要形成于太古宙的表壳岩系,下部由大量超基性-基性火山岩构成,上部中-酸性火山-沉积岩逐渐增加.以绿岩带为代表的太古宙表壳岩系占克拉通总体的~30%,记录了早期地球岩浆活动和表生环境的丰富信息,是揭示地壳形成和演化规律的重要研究对象.鲁西是华北克拉通太古宙表壳岩保留较好的地区之一,其主体形成于~2.7和~2.5Ga两个时期,早期表壳岩由泰山岩群下部变科马提岩-玄武岩、少量变碎屑沉积岩和孟家屯岩组变基性岩和变碎屑沉积岩组成,原岩记录的火山岩浆作用与地幔柱有关,反映鲁西在新太古代早期地壳形成具有垂向增生的特点.晚期表壳岩由泰山岩群上部变长英质火山沉积岩、变碎屑沉积岩与少量BIF和济宁岩群变长英质火山岩、变碎屑沉积岩和大规模BIF组成,其中泰山岩群变火山沉积岩的地球化学组成与现代岛弧环境产出的钙碱性岩系类似,指示鲁西的大陆地壳在新太古代晚期可能已发生一定规模的水平运动;鲁西七星台地区变碎屑沉积岩和周围混合岩浅色脉体记录区域高角闪岩相变质-深熔作用的时代可限定在2.53~2.50Ga,与大规模壳熔花岗岩的形成时代一致,标志鲁西在新太古代末已形成统一的陆壳基底.
The greenstone belt is mainly formed in the Archean crustal rocks, the lower part is composed of a large number of ultrabasic-basic volcanic rocks, and the upper intermediate-acidic volcano-sedimentary rocks are gradually increased. The Archean crustal rocks Accounting for ~ 30% of the total craton, recording abundant information on magmatic activities and superficial environments in the early Earth, and is an important research object for revealing the formation and evolution of the crust. Luxi is well preserved in the Archean crust of the North China Craton Its main body was formed in two periods of ~ 2.7 and ~ 2.5Ga. Early crustal rocks were formed by the lower part of the Taishan Group Swimmachite-basalts, a few metamorphic sedimentary rocks and the Mengjitunyan group metamorphic rocks And detrital sedimentary rocks, and the volcanic magmatism recorded by the original rocks is related to the mantle plume, reflecting that Lusi had vertical accretionary formation in the Early Neo-Archean crust. Late-stage crustal rocks were altered from the upper part of the Taishan Group to the volcano Sedimentary rocks, variable clastic sedimentary rocks and a small amount of BIF and Jining Group variable metamorphic volcanic rocks, variable clastic sedimentary rocks and large-scale BIF, in which the geochemical composition of Taishan Group volcanic sedimentary rocks and modern island arc environment, the output of calc-alkali Sex rock series It is indicated that the continental crust of Luxi may have experienced a certain level of horizontal movement in the Late Neo-Archean. The metamorphic-diagenetic amphibolite facies of the Qixingtai area in the Luxi area and the lithic veins of the surrounding mixed rocks The age can be limited to 2.53 ~ 2.50Ga, coinciding with the formation of large-scale crustal granite, indicating that Luxi formed a uniform continental base at the end of Neoarchean.