贵州及邻区奥陶纪桐梓期岩相古地理特征

The Features of Lithofacies Paleogeography of Tongzi Age in Guizhou Province and Its Adjacent Areas

在前人工作的基础上,本文对贵州及邻区奥陶纪桐梓期的古生物群落及沉积岩石学的纵横变化进行系统研究,对其岩相古地理格局获得了较为系统的认识,共划分出三个相体系八个相带。

On the basis of predecessors' work and having done a lot of field and laboratory work, the author will deal with the features of lithofacies palaeogeography of Tongzi Age in this paper. According to the features of vertical and horizontal distributions of biological associations and depositional rock associations, the lithofacies palaeogeography pattern of Tongzi Age in Guizhou and its adjacent areas can be divided into following depositional systems and facies: Ⅰ. The depositional system of epicontinental clastic littoral: littoral fades and offshore facies. Ⅱ. The depositional system of carbonate platforms: restricted marine platform facies, opening marine platform fades, semi-restricted marine platform facies and platform marginal interclastic beach facies. Ⅲ. The depositional system of semi-deep sea and deep sea basins: semi-deep sea basin facies and deep sea basin facies. This special pattern of lithofacies palaeogeography was gradually formed from early to late and from east to west under the sedimentary condition that marine space was expanded and old land was reduced.