【摘要】 分布于四川西北部若尔盖地区秦岭褶皱带西段的白依沟群,由一套浅变质的陆源碎屑及火山质碎屑岩及其过渡类型的岩石组成。白依沟群过去认为是奥陶-志留纪的沉积。自1982年在西秦岭开展1:5万区调和科研工作以来,通过岩性,岩相以及区域地层对比,笔者认为此套岩系与川西下震旦统苏雄组和开建桥组相当.因此,首次提出秦岭西段有早震旦世陆相沉积,证实了当时甘孜松潘一带为一古陆。更多还原

【Abstract】 Bai Yigou group situated in the west part of the Qinlin foldbelt in the Northwest of Rouergai region is a set of low grade metamorphosed petroclastic terrigenous rocks, pyroclastic rocks and their transitional types. Previously it has been regarded as Ordouician-Silurian. Since1982 1: 50000 maping has been carried out in this area. On the basis of lithological and lithofacies study, it is shown that the Bai Yigou group is fully comparable with the Suxiong and Kaijianqiao group of lower Sinian in the west part of Sichuan.The authors firstly consider that terrestrical facies sediments did develop during lower Sinian in the west part of Qinlin Mountian and conclude that a palaeoplate at that time exisited in the Ganzi Songpan area.更多还原