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苏鲁褶皱带形成于元古宙 (2 2 33～ 185 5Ma)典型优地槽构造环境 ,主要由石榴橄榄岩、石榴辉石岩、榴辉岩等侵入岩 (柯石英深度相地幔岩浆房中形成 )和它们的火山沉积建造围岩一起经褶皱、变质而形成。变质作用经历了先蓝片岩相 (前花岗岩 )后片麻岩混合岩相过程。由于变质作用的不规律性 ,苏鲁褶皱带可分为 2个构造带 :(1)东部构造带 (蓝片岩 )和 (2 )西部构造带 (片麻岩混合岩 )。根据A·都城秋穗所识别的变质带系统 ,可将其作为一个双变质带。东部构造带以出现许多块状、条带状榴辉岩辉石岩橄榄岩组合的残余岩块为特征 ,其中还残留着高压的矿物 (石榴石、绿辉石、柯石英 ) ,而且有被混合岩和各种交代岩替代的显著标志。在中生代 ,苏鲁元古褶皱带受造山作用的影响活化 ,导致许多花岗岩体的侵入 ,使交代岩广泛发育。
The Sulu fold belt is formed in the typical favorable trough tectonic environment of the Proterozoic (2233-585 Ma), mainly composed of intrusive rocks such as pomegranate peridotite, garnet pyroxenite and eclogites (in the coesite-depth mantle magma chamber Formed) and their volcanic sedimentary rock built together by the formation of folds, metamorphism and formation. The metamorphism experienced the process of mixed lithofacies of gneisses from the first blueschist facies (former granite). Due to the irregular metamorphism, the Sulu fold belt can be divided into two structural zones: (1) the eastern tectonic belt (blue schist) and (2) the western tectonic belt (gneiss). According to A. Metropolis Akishita metamorphic belt system can be used as a double metamorphic belt. The eastern tectonic belt is characterized by the presence of many massive and banded eclogite-pyroxen peridotite assemblages of residual rocks, in which high-pressure minerals (garnet, omphacite, coesite) remain, Mixed rocks and a variety of metasomatism replacement of significant signs. In the Mesozoic, the Sulu Paleozoic fold belt was activated by orogeny, resulting in the intrusion of many granite bodies and extensively developed metasomatism rocks.