柴达木盆地北缘“沙柳河岩群”的重新启用

On reuse of Shaliuhe Group in the northern margin of Qaidam basin

柴北缘变质基底岩系中的表壳岩包含了岩石组合、沉积建造、变质程度和地质时代不同的两套岩石组合。其中,分布在柴达木地块的沙柳河、鱼卡河等地的以大理岩、石英岩和含石榴石英片岩为主含榴辉岩透镜体的表壳岩系,时代限定在1.0～1.3Ga,与分布在欧龙布鲁克微陆块的全吉山、德令哈等地形成时代大约2.3～2.4Ga的达肯大坂岩群有着明显的不同,后者以斜长角闪岩、石榴石英片岩和黑云变粒岩为主,并具有较强的钾质混合岩化。由于前者岩石组合清楚,沉积建造特征明显,构造意义独特,且有一定的区域分布性和可比性,所以具备建立新的岩群的条件。根据定名优先的原则,决定重新启用沙柳河岩群。

There is very complicated composition in the metamorphic basement of the northern margin of Qaidam. In the south part of the area appears marble, garnet-quartz-mica-schist, quartzite, ecligite and other paragneiss system and they are named Shaliuhe Group. With the Neoproterozoic granite-gneiss, it constituents Qaidam block mass. In Oulongbuluke micro-block appears mid-high-metamophic crust system with extensive potassic migmatization and they are named Dakendaban Group.