扬子地区晚奥陶世碳酸盐台地淹没事件及其地质意义

碳酸盐岩台地广泛发育及其淹没事件是扬子地区晚奥陶世地层的重要特征之一.基于岩石学、沉积学特征和古生物资料等对扬子地区晚奥陶世碳酸盐岩台地沉积演化、淹没事件及其油气地质意义进行了分析.结果表明:扬子地区晚奥陶世沉积演化分为宝塔一临湘期碳酸盐台地沉积和五峰期深水、浅水陆棚沉积两个阶段;淹没事件开始于五峰初期,主要受控于构造...

The Late Ordovician drowning of the Yangtze carbonate platform and its geologic significance

The drowning of the carbonate platform is one of the most spectacular geological processes in the Late Ordovician on Yangtze block.Based on sedimentological and palaeontologic data，the drowning process of Late Ordovician carbonate platforms and geologic consequence in Yangtze area，as well as its significance for oil exploration，were documented.These data indicate the following facts：(1)during the Baota and Linxiang periods of Late Ordovician，epicontinental carbonate platform occupied most of the Yangtze block； (2)Drowning occurred in the early stage of Wufeng period，due to a rapid rise in sea level resulted from tectonic flexure； (3)during the drawing stage，widespread black shales of Wufeng Formation were deposited on the Yangtze block，which are served as favourable source rocks for hydrocarbons in the region.