中国南方海相层系油气成藏组合类型与勘探前景

Types of marine plays in southern China and exploration prospects

中国南方海相层系以志留系区域滑脱层为界,可分为上、下两个构造层,据不同地区上、下构造层形变特征与强度及其组合特征,可将其地质结构分为单层稳定、双层连续、双层断褶、单层叠瓦、双层冲滑、单层冲断和二元推覆等7种类型。印支以来多期沉降与隆升产生了“早降晚抬”和“早抬晚降”2大类6种形式的埋藏演化史类型。海相地层原始建造、后期构造运动改造与上覆陆相地层的叠加形成了原生型、改造型、再生型和后生型4种类型的成藏组合。其中原生型成藏组合油气保存条件好,勘探前景好。中、下扬子区再生型和后生型成藏组合具有一定的勘探前景。

Being bounded by the Silurian regional detachment, the marine stratigraphic series in southern China can be divided into lower and upper two structural layers. According to the strength and characteristics of deformation of the structural layers, as well as their combination features, the geologic configuration of marine stratigrahpic series in southern China can be classified into 7 types, i.e. single layer stable, double layer continuous, double layer fault-folded, single layer imbricated, double layer thrust-slipped, single layer thrust faulted and binary nappe types. Muhiphase subsidence and upheaval since Indosinian have led to the formation of 6 kinds of burial evolution history, which can be grouped into two large types, namely ＂early subsidence - late upheaval＂ and ＂early upheaval - late subsidence＂. The initial buildup of marine sedimentary formations, later reconstruction by tectonic movements and the superimposition of the overlying non-marine formations have resulted in 4 play types, including primary type, reconstructed type, regenerated type, and epigenotype; of which the primary play type has good oil and gas preservation conditions, and thus has good exploration prospects. The plays of regenerated type and epigenotype in the Middle and Lower Yangtze areas have certain exploration prospects, too.