摘要
川东地腹区长兴组生物礁的主要成岩作用为泥晶化、填积、胶结、白云化和溶蚀作用。其中白云化和溶蚀作用对次生孔隙发育起控制作用。上覆致密碳酸盐岩、泥质岩类等是很好的盖层,因此,礁气藏是典型的岩性-成岩圈闭型气藏。对北部、东部的“干死型”和南部、西部的“淹死型”生物礁成岩序列也有叙述。
The main diagenetic processes of Changxing reefs are: micritization, filling, cementation,dolomitization and dissolution. Among them dolomitization and dissolution are the controlling factorsfor the development of secondary porosity. The dense carbonates and mudstones constitute the cap rocksof the reef reservoirs. Hence, the natural gas pools accumulated in the reefs are of lithologic-diagenetictraps. Diagenetic sequences of both dried and drowned reef types located in the north-east and south-west respectively are presented.
基金
地质行业科学发展基金
关键词
礁岩
成岩作用
孔隙
演化
天然气藏
natural gas pool
reef facies
diagenetic pattern
porosity evolution
