贵阳花溪地区下中三叠统露头层序地层研究

贵阳花溪地区下、中三叠统可划分为碳酸盐台地相、台缘相和盆地相三个沉积相区。在对不同相区内典型剖面详细观测、层序界面识别基础上,将下、中三叠统划分为5个Ⅰ型沉积层序和1个Ⅱ型层序。通过研究实测剖面纵向的沉积相变和横向低位岩楔的位置迁移,讨论了区内相对海平面变化。研究区在早-中三叠世经历了一次完整的二级海平面升降旋回:早三叠世与全球海平面变化基本一致,呈上升趋势;中三叠世由于构造作用,海平面总体呈下降趋势,表现出区域特殊性。

Outcrop sequence stratigraphy of the Middle-Lower Triassic strata in the Huaxi region,Guiyang,Guizhou

The Middle -Lower Triassic strata in the Huaxi region, Guiyang, Guizhou are assigned to three sedimentary facies： carbonate platform, platform-margin and basin facies, including five type I and one type II depositional sequences. The study area once experienced a complete second-order cycle of sea-level fluctuation during the Early - Middle Triassic ： a rising trend during the Early Triassic and a falling trend due to the effects of regional tectonic movement during the Middle Triassic.