云贵大堤滩上的成岩作用

DIAGENESIS ON YUNGUIDADITAN

通过对贵阳花溪垄头剖面的野外地质和室内薄片观察,对发育在中三叠统垄头组中部的云贵大堤滩沉积成岩作用进行研究,认为垄头组主要经历了:渗流环境的准同生岩溶、胶结、充填和白云岩化;潜流环境的胶结、充填与白云岩化;埋藏环境的溶蚀及白云岩化;表生环境的区域地下水去白云岩化及近地表岩溶等成岩作用。在此基础上建立了垄头组成岩序列。

Based on both outcrop observation and thin-section analysis of Longtou section in Huaxi area, Guizhou, a study on sedimentary diagenesis of Yunguidaditan has been implemented for the middle of middle Longtou Formation. Results illustrate that the formation experienced mainly (1) penecontemporary dissolution, cementation, packing and dolomitization under a percolation environment; (2) cementation, packing and dolomitization under a phreatic environment; (3) dissolution and dolomitization under a burial environment; and (4) regional underwater dedolomitization and near-surface dissolution under a surface environment. At last, a set of diagenetic sequence has been established for Longtou Formation.