Duyun movement occurred between the late Ordovician and early Silurian, which resulted in an united uplift belt (commonly called Qian Zhong Oldland) from Dian Zhong uplift to Qian Zhong uplift. This uplift belt separated southeast Yunnan--south Guizhou region from northeast Yunnan--north Guizhou--south Sichuan region, which belong to two different depositional--tectonic domains, one in the south, and another in the north. In the south domain, lower and middle Cambrian, middle and upper Silurian, and lower Devonian series developed. There is an unconformity between the Cambrian and Silurian, and the Ordovician and Early Silurian are missing. On the contrary, in the Luquan --Wuding region of the  north domain, the Ordovician is complete, and is unconformably overlain by the Devonian, with the Silurian missing. The two different depositional sequences in north and south domains indicate that these two domains developed independently. In the middle--late Silurian, the area south of the Qian Zhong uplift should belong to  the Upper Yangtze Plate and the foreland flexural basin in Yunnan--Guizhou--Guangxi block. This area extended northeast from Qujing via Yadu of Hezhang--Guiyang to west Hunan, and southward linked with Huchun Sea in Yunnan. The area  north of the Qian Zhong uplift should belong to the marginal facies of the foreland basin (Sichuan south--Guizhou north) in the Upper Yangtze Plate.