| Because of the Duyun Movement at the end of the Ordovician Aijiashan Epoch and the Guangxi Movement at the end of the Silurian Period, the Silurian System in Central Guizhou Uplift and its adjacent areas are not integrated. The research area can be divided into two parts: the Qianbei area in the north of the Central Guizhou Uplift and the Qiannan area in the south. In the north area, the transition from Ordovician System to Silurian System is continuous on the whole, but the strata in the south area lack the Ordovician Qiantangjiang Series and the foot part of the Silurian System, as a result of the Duyun Movement. Besides that, rocks and facies are obviously different between the north and south area. In the north, Silurian System is composed of Longmaxi Formation, Xintan Formation, Songkan Formation, Shiniulan Formation and Hanjiadian Group, whereas the south is Gaozhaitian Group and Wengxiangqun Group. Based on the background of the confined foreland basin, seven 3rd-order sequences (SS1-SS7) can be discerned in Qianbei area, but it is very different in Qiannan . In the south, it can only be divided to three 3rd-order sequences (SS4-SS6). According to the natures of the 3rd-sequence, two kinds of facies-change surfaces and two kinds of diachrononism in stratigraphical records, the sequence stratigraphic framework can be established. The sequence stratigraphic framework indicates that the 3rd-order sequences SS1-SS4 only distribute in Qianbei area. It shows that in the period of SS1-SS4 forming, the sea-level continuously rise, so that the seawater transgress to Qiannan area, making the integrated Dianqiangui old land divided. When the 3rd-order sequences SS5-SS6 develop, the sea-level fall and the research area changes from formal shallow sea to confined shallow sea. The Guangxi Movement make the lithosphere uplift, so the upper Silurian strata are erosion and weathered and the top of the sequence is directly covered by Permian System.
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