论文部分内容阅读
松辽盆地南部基底主要由浅变质火山-沉积建造及花岗岩类等组成,对于是否存在早前寒武纪基底没有定论.采用高分辨率二次离子探针(SHRIMPⅡ)方法对松辽盆地南部四5井岩心中的变质闪长岩样品的精确定年结果表明,该变质闪长岩年龄为(1839±7)Ma,说明其侵位于古元古代.此外,该样品具有古老的Nd模式年龄(TDM1:2999Ma;TDM2:2849Ma).这些资料表明松辽盆地南部存在早前寒武纪基底.
The basement of the southern Songliao Basin is mainly composed of the metamorphic volcanic-sedimentary deposits and granitoids, etc. There is no conclusion as to whether there is an early Precambrian basement or not.Using high resolution second ion probe (SHRIMPⅡ) The precise dating of the metamorphic diorite samples in the well core shows that the metamorphic diorite is (1839 ± 7) Ma, indicating that it was intruded in the Paleoproterozoic. In addition, the sample has the ancient age of Nd mode (TDM1: 2999Ma; TDM2: 2849Ma). These data indicate that there was an Early Precambrian basement in the southern Songliao Basin.