A special,cliffy,high-obliquity and onlap stratigraphic contact relationship,escarpmentive pseudounconformity,is developed generally between middle Devonian(Beiliu formation,late Devonian liujiang formation and Rongxian formation) and lower Carboniferous(Baping formation).
桂西下雷、土湖锰矿区于上泥盆统榴江组—五指山组—融县组—下石炭统巴平组与中泥盆统北流组之间,发育了一种特殊的、呈陡崖状的高角度"上超"状的地层接触关系——陡崖式假不整合。
