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将旋回地层学（ｃｙｃｌｏｓｔｒａｔｉｇｒａｐｈｙ）和层序地层学（ｓｅｑｕｅｎｃｅｓｔｒａｔｉｇｒａｐｈｙ）有机地结合起来并应用沉积学和地层学的基本理论研究了陕西省商南地区上泥盆统王冠沟组旋回层序级别的划分、层序边界特征、三级旋回层序内部组成特征以及米级旋回的沉积特点。王冠沟组可以识别出１．５个三级旋回层序，４个四级旋回层序，共发育８６个米级旋回，归属８大类。三级旋回层序发育低水位体系域（ＬＳＴ）、海进体系域（ＴＳＴ）、高水位体系域（ＨＳＴ）和陆架边缘体系域（ＳＭＳＴ）。第一个三级旋回层序的底界面为Ⅰ型层序界面（ＳＢ１），顶界面为Ⅱ型层序界面（ＳＢ２），明显地具间断－加积旋回（ＰＡＣ）沉积特征。通过详细的旋回层序研究以及与中国黔南和世界晚泥盆世弗拉斯阶海进－海退旋回进行比较研究，并结合区域地层对比研究，商南地区上泥盆统王冠沟组旋回发育不完整，推测可能地层发育不全。
Cyclostratigraphy and sequencestratigraphy are organically integrated and the basic theory of sedimentology and stratigraphy are applied to study the division of the sequence of the Wanggougou formation in the Upper Devonian in Shangnan area, Sequence boundary features, the internal composition of the third-order cycle and the sedimentary characteristics of the Mi-cycle. The Wangguangou Formation can identify 1.5 third-order cycles and four fourth-level cycles, a total of 86-meter cycles, belonging to 8 categories. The third-order cycle sequence developed LST, TST, HST and SMST. The bottom interface of the first three-stage cycle is type Ⅰ sequence interface (SB1), and the top boundary is type Ⅱ sequence boundary (SB2), clearly with discontinuous-accretionary cycles (PAC). Through the detailed study of the cycle sequence and the comparison of the seafloor-metasomatism with the Flusian order of the Late Devonian in southern Guizhou and the world in the world, and combining with the regional stratigraphic correlation study, the Upper Devonian Wanggougou Formation in Shangnan area Incomplete development, presumably stratum hypoplasia.