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沉积序列、沉积相、古水流和物质组成的研究结果表明,西秦岭大草滩群和铁山群分别是由冲积扇和近岸浊积扇形成的陆相碎屑岩组合和滨海相浊积岩。李子园群岛弧火山岩不仅是形成大草滩群的沉积物源,而且也是大草滩群沉积盆地的基底。构造变形特征和与上、下地层接触关系综合研究显示,大草滩群是秦岭晚古生代弧前增生过程中形成的一个逆冲席顶盆地。大草滩群可与祁连山中晚泥盆世沙流水群和雪山群相比较,向东、南分别与同期异相桐峪寺组、铁山群相对应,显示出由北向南、由西向东的构造迁移特征。
Sedimentary sequences, sedimentary facies, paleocurrent and material compositions show that the Taicaotan Group and the Tieshan Group in the West Qinling are continental clastic assemblages and turbidite units formed by alluvial fans and nearshore turbidites, respectively . The argillaceous volcanic rocks of the Plum Group Archipelago are not only the sediment source for the formation of Grandmas Beach Group, but also the base of the Sedimentary Basin of Grandmas Beach Group. Tectonic deformation characteristics and contact with the upper and lower stratigraphic comprehensive study shows that the Dachan group is the Qinling Paleozoic during the Precambrian hyperplasia in the formation of a thrust top basin. The Dachan group can be compared with the middle-late Devonian sand-flow group and the Xueshan group in the Qilianshan Mountains. The eastern and southern regions respectively correspond to the Tongxiang-Yushan Formation and the Tieshan Group in the same period, showing that from north to south and from west to east Structure migration characteristics.