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阿尔金含菱镁矿的石榴石二辉橄榄岩呈透镜体状与石榴石辉石岩和含榴长英质片麻岩伴生,一起出露在江格萨依东约100多公里处的元古界片麻岩中,它与西段江格萨依一带的榴辉岩共同构成阿尔金南缘高压-超高压变质带.岩相学研究揭示该岩石经历了复杂多阶段的变质演化,其中峰期变质矿物组合是由粗粒 Grt+Ol+Opx+Cpx±Mgs组成,该期Opx的 Al2O3含量很低（0.30％～0.66％）,估算的P-T条件为 3.8～5.1GPa和880～970℃.同时,考虑该期石榴石含有单斜辉石和金红石的棒状出熔物以及菱镁矿的外围分布有由白云石和斜方辉石构成的反应关系,表明该岩石经历了超高压变质作用.综合区域地质、同位素年代学和岩石化学资料,进一步结合柴北缘地区榴辉岩和片麻岩锆石中柯石英包体的发现,证实中国西北部存在一条被中-新生代阿尔金走滑断裂截切错移的巨型超高压变质岩带.
Allginian garnet lherzolites containing magnesite are lenticular in shape and associated with garnet pyroxene and pomegranate feldspathic gneisses, revealing a combination of Proterozoic Epidemisis about 100 km east of the Giangsar Rock, which together with the eclogite in the Geshea area of the western segment constitute the high-pressure-ultrahigh-pressure metamorphic belt along the southern margin of the Altyn Tagh. Research on petrography revealed that the rock underwent complex multi-stage metamorphic evolution with metamorphic minerals The composition is composed of coarse Grt + Ol + Opx + Cpx ± Mgs, the Al2O3 content of this Opx is very low (0.30% ~ 0.66%), and the estimated PT conditions are 3.8 ~ 5.1GPa and 880 ~ 970 ℃. This period of garnet contains clinopyroxene and rutile rod-shaped out of melt and magnesite peripheral distribution of the dolomite and orthopyroxene structure of the reaction, indicating that the rock underwent ultra-high pressure metamorphism.Comprehensive regional geology, isotopes The chronological and petrochemical data, combined with the discovery of coesite inclusions in eclogites and gneiss zircons from the northern margin of the Qaidam Basin, confirmed the presence of a cosecrust that was cut and shifted by the Meso-Cenozoic Altun fault in the northwestern part of China Giant UHP metamorphic belt.