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浙皖边界上二叠统与下三叠统之间,从岩性组合、沉积相的变化,显示有一个平行不整合面,局部地区还存在有微角度不整合现象。长兴灰岩由东向西变薄尖灭,致使殷坑组与龙潭组直接接触。表明长兴灰岩形成后,由于地壳曾一度上升而遭受风化剥蚀。殷坑组底部存在一层底砾岩及褐铁矿等古风化壳沉积物。这些特征反映了二叠系与三叠系间存在着沉积间断,这个间断是苏皖运动的结果。作者认为本区二叠系与三叠系间不存在“过渡层”。
Between the Upper Permian and the Lower Triassic in the Zhejiang-Anhui border, there is a parallel unconformity surface from lithologic assemblages and sedimentary facies, and there are some micro-angle unconformities in some areas. Changxing limestone thinning out from east to west, resulting in Yin Hang group and Longtan group direct contact. It shows that Changxing limestone was weathering and denudation due to the once rising of crust. At the bottom of Yinkeng Formation, there exists an ancient weathered crust sediment such as base conglomerate and limonite. These characteristics reflect the sedimentary discontinuity between the Permian and Triassic. This discontinuity is the result of the Su-Wan movement. The author thinks there is no “transitional layer” between Permian and Triassic in this area.