摘要
主要的成岩作用类型有压实压溶作用、裂隙作用、胶结作用及溶解作用。成岩作用阶段可划为三期:早期大致为茅口期;中期为晚二叠世初至白垩纪末;晚期为白垩纪末或第三纪初至第四纪。与此相应所经历的成岩环境演化序列大致为:海水成岩环境→浅埋藏成岩环境(浅埋I)→深埋藏成岩环境→浅埋藏成岩环境(浅埋I)→晚期大气淡水成岩环境。指出了深埋有机酸溶解作用形成的次生溶孔是本区最有意义的油前孔隙,大多被沥青所充填。
The main types of diagenesis include compaction and pressure solution, fracturing, cemen- tation, and dissolution. The diagenesis underwent three periods: (1)the Maokou Stage; (2)the early Late Permian to the end of Cretaceous; (3)the end of Cretaceous/ the early Tertiary to the Quaternary. In cor- respondence with it, the evolution succession of diagenetic environments was as the following: sea water→ shallow bury(I)→deep bury→shallow bury(Ⅱ)→late fresh atmosphere water. It is pointed out that the secondary corroded hollows created by dissolution of deep buried organic acid have been the most sig- nificant pores before oil forming, and most of them have been filled with asphalt.
关键词
早二叠世
生物礁
成岩作用
孔隙演化
藻丘
Anhui
(Tongling)
Early Permian
organic reef
diagenesis
pore evolution
