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湘西中、上寒武统花桥组和车夫组主要由斜坡相和盆地边缘相的碳酸盐岩、泥质碳酸盐岩及钙质泥岩组成。重力流沉积十分发育，其中花垣排碧剖面以碎屑流砾屑灰岩和近源浊积岩为主；永顺王村剖面以浊流沉积为主；桃源瓦尔岗剖面则以远源浊积岩为主。成岩作用主要为海底埋藏胶结作用、新生变形作用和白云石化作用。排碧剖面大多数岩样酸不溶物重量含量在１０％以下，王村和瓦尔岗剖面大多数岩样在１０％以上。全岩δ１８Ｏ值介于－１１．２‰至－５．６‰（ＰＤＢ）之间；δ１３Ｃ值为－１．９‰至３．４‰（ＰＤＢ）。从Ｌｉｎｇｕａｇｎｏｓｔｕｓｒｅｃｏｎｄｉｔｕｓ带开始，δ１３Ｃ有较大的正漂移，漂移值达３‰（ＰＤＢ）以上。沉积花桥组和车夫组时，湘西过渡区经历了４次海平面升降事件，台缘斜坡逐渐变陡，由缓坡型逐渐发展为镶边型和沟槽型。在湘西的诸多剖面中以王村剖面最适合于作为中、上寒武统界线层型候选剖面，界线选择在花桥组顶部。
The Middle and Upper Cambrian Huaqiao Formation and the Che-Fu Formation mainly consist of carbonate rocks, muddy carbonate rocks and calcareous mudstone on the slope facies and the margin of the basin. Gravity flow sedimentation is well developed, of which the Paraguan Paixi profile is dominated by detrital boulder limestone and near-source turbidite; the Yongshun Wangcun section is dominated by turbidite; the Taoyuan Valgang section is dominated by far-source turbidite Rock-based. The diagenesis is mainly the seabed burial cementation, the new deformation and the dolomitization. Most of the samples in Paixi profile have the content of acid insoluble matter less than 10%, and most of the samples in Wangcun and Wulgang profiles are above 10%. Total rock δ18O values ranged from -11.2 ‰ to -5.6 ‰ (PDB); δ13C values ranged from -1.9 ‰ to 3.4 ‰ (PDB). Starting from the Linguagnostus reconditus zone, δ13C has a larger positive drift with a drift of more than 3 ‰ (PDB). During the deposition of Huaqiao group and Qiafu group, the transitional region of western Hunan underwent four sea level rise and fall events, and the margin of the margin gradually became steeper, gradually changing from a gentle slope type to a striped type and a groove type. Among the many sections in western Hunan, the Wangcun section is the most suitable for the mid-and upper-Cambrian boundary layer candidate profiles with the boundary selected at the top of the Huaqiao Formation.