下扬子改造型海相盆地的多期生烃及晚期生烃资源评价

下扬子盆地属改造型海相盆地之一,具有多期生烃、多次成藏的特点。印支运动改造前的成藏属于早期成藏,印支运动之后在陆相覆盖条件下的成藏过程属于晚期烃源岩的晚期成藏过程。研究表明,早期烃源岩和晚期烃源岩均对海相油气资源聚集有重要贡献。晚期成藏的油气资源保存性相对稳定,其资源量至少达7.04×10~8t以上,是海相油气较为现实的勘探目标与对象。它们主要分布于苏北的兴化、海安及苏南的湖熟、丹阳、江阴等地区。

Evaluation on Multi-and Later-Stage Hydrocarbon Generation in the Lower Yangtze Modified Marine Basin

The Lower Yangtze basin is a modified marine basin, characterized with multi-stage hydrocarbon generation and reservoir formation. The earlier reservoir formation occurred before Indosinian movement and the later one post-Indosinian movement. Research shows that both the earlier and later source rocks delivered important contribution to marine oil/gas accumulation. The later formed oil/gas reservoirs, with relative stable preserving conditions and over 7.04 billion tons of resources, are the practical marine exploration targets and objectives in marine sediments. They are mailtly distributed in Xinghua and Hai'an areas of the Subei Basin and Hushu, Danyang and Jiangyin areas of the Sunan Basin.