南秦岭“大堡组”早期被认为属于奥陶纪地层.经过详细的野外地质工作,查明“大堡组”由灰-深灰色的泥岩和粉砂岩以及裹于其间的灰岩、硅质岩、火山岩和凝灰岩块体组成.在灰岩块体中新发现了中泥盆世的牙形石和珊瑚等化石,表明“大堡组”形成时代应为晚古生代.因此,结合现有的资料推断南秦岭“大堡组”为晚古生代或早中生代形成的增生混杂带. In the early Qinling Mountains, the “Great Fort Group” was considered to belong to the Ordovician strata. After detailed geological work in the field, it was found that the “Great Fort” consists of gray-dark gray mudstone and siltstone, and the ash Rocks, silicalites, volcanic rocks and tuff blocks.The fossils of the Central Devonian conodonts and corals were newly discovered in the limestone blocks, indicating that the “Great Fort” formation age should be the Late Paleozoic. Based on the available data, it is concluded that the South Qinling Mountains and the “Da Bao Formation” are hyperplastic mixed belts formed in the Late Paleozoic or Early Mesozoic.