中文摘要：

江浪穹窿位于扬子西缘松潘一甘孜造山带东南缘,本次研究对江浪穹窿南部江浪岩组黑云石英片岩进行LA-ICP-MS U-Pb碎屑锆石测年。结果显示,这些锆石的年龄主要介于2 925~537 Ma之间。对比分析揭示沉积物源应来自扬子板块西北缘的元古代地层,且多为岩浆事件的产物,活动时期主要集中于2 479 Ma、810 Ma和548 Ma左右,变质事件则可能发生于918 Ma、608 Ma和100 Ma左右。2925~2462 Ma的老年龄锆石暗示区内可能存在古元古代甚至太古代的老基底。6个年轻年龄集中于559~537 Ma,加权平均值（548±9）Ma（MSWD=1.4,2σ）,因而本文将该年龄（新元古代）作为江浪组最老的沉积时限。

英文摘要：

Jianglang dome is located in southeastern Songpan-Ganzi orogen, western Yangtze block. The LA-ICP-MS detrital zircon U-Pb study on biotite schists from Jianglang group shows that they are mainly dated from 537-2925 Ma. Comparative analyses reveal that the sources of these sedimentary rocks are mainly from Neo-proterozoic strata of Yangtze block. These zircons were mainly derived from magmatic events at about 548 Ma, 810 Ma and 2479 Ma, whereas the metamorphic events mainly occurred at about 918 Ma, 608 Ma and 100 Ma. The oldest age ranging from 2 925 to 2 462 Ma indicates that the Paleo-proterozoic even Archean basement exists in Songpan-Ganzi area. In addition, six younger zircons yielded ages of 537- 559 Ma with a mean of （ 548 ± 9） Ma （ MSWD = 1.4, 2σ） Thus, we propose that the Jianglang Formation belongs to Proterozoic Liwu group.