贵州太康运动的地层学效应——兼论“黔中古陆”的形成

The Stratigraphic Effect of the Taconic Movement in Guizhou——A Discussion on the Formation of Palace-land of Central Guizhou

太康运动是发生在中奥陶世末期的一次全球规模的地壳运动,相应地在贵州又称为都匀运动。由此而形成的贵州南部的早、中奥陶世及志留纪地层间的平行不整合,以及不整合面上、下的古地质特征是太康运动在贵州的主要地层学效应。 太康运动使中奥陶世以前的北东—南西向的古地理构局转变为南北向的格局。由于太康运动形成的地壳抬升,使榕江—天柱一带隆起成江南古陆,黔中地区的修文—瓮安一带隆起形成黔中古陆。 本文以太康运动的地层学效应为基础,着重讨论了黔中古陆的形成。

The Taconic movement, also called the Duyun movement in Guizhou, was a worldwide crustal movement which occurred in the last period of the Mid-Ordovician. The parallel disconformity between the Mid-Ordovician and the Silurian in the south of Guizhou and the characteristics of palaeogeology on or beneath the disconformity were the main stratigraphic effect of the Taconic movement in Guizhou. The Taconic movement caused the northeastward-southwestward palaeographk pattern before the Mid-Ordovician to change into the southward-northward pattern of the Silurian. The crustal uplift due to the formation of the Taconic movement caused the zone of Rongjiang-Tianzhu to rise to form the Jiangnan palaeoland and the zone of Xiuwen-Wengan in Central Guizhou to rise to form the palaeoland of Central Guizhou. On the basis of the stratigraphic effect of the Taconic movement, this paper deals with the formation of the palaeoland of Central Guizhou.