摘要
1:5万区域地质调查工作中,在柴达木陆块北缘首次发现古元古代变质镁铁—超镁铁质岩,获得成岩年龄为1952±15Ma,其岩石化学、地球化学特征反映出岩浆来源于亏损地幔,反映出该地区克拉通在古元古代(19亿年)发生了一次强烈的裂解(洋)事件,对于研究柴达木盆地北缘元古代结晶基底地质构造演化及进一步探讨柴达木盆地的起源及构造演化过程提供了重要地质线索。
A Early Proterozoic metamorphic mafite-ultramafite with a diagenetic age of 1952 ± 15Ma. B.P. has been firstly found in the northern margin of Qaidum Basin during 1:50000 regionalgeological survey. Its petrochemistry and geochemistry reflect that the magma stem from loss mantle andthe craton in this region was subjected a strong splitting event in Early Proterozoic Era(1900 Ma. B.P.). It provide an important geological basis for such studies as the tectonic evolution ofProterozoic crystalline basement and the origin and tectonic evolution of Qaidum Basin.
