江汉盆地南部上古生界海相烃源岩生烃史与晚期生烃潜力

动态地评价江汉盆地南部上古生界烃源层在不同地质历史时期的生烃过程，特别是晚期生烃对早燕山期形成的很多局部构造能否得到后期的烃类充注是判断其含油气性的关键，因而生烃演化、特别是晚期生烃、晚期成藏对研究区海相上古生界勘探显得十分重要。从烃源岩的成熟度变化、地层推覆倒转剖面2个方面证明晚期生烃在研究区存在，但不同剖面之间、同一剖面不同层系之间晚期生烃现象存在差异。埋藏史研究认为，研究区内主要存在持续深埋型、深埋—剥蚀夷平型、深埋—抬升—深埋型、深埋—抬升—浅埋型4种类型的埋藏演化过程，其中前2类对于晚期生烃有十分重要的意义。生烃史与晚期生烃潜力计算结果进一步表明，上古生界烃源层晚期生烃潜力当阳地区略高于沉湖地区。

Hydrocarbon Generation History and Late Hydrocarbon Generation Potential of Neopaleozoic Marine Source Rocks in the South of Jianghan Basin

This paper dynamically evaluates the hydrocarbon generation process of Neopaleozoic source rocks in the south of Jianghan Basin during different geologic times. Late hydrocarbon generation is especially important for the hydrocarbon filling of local structures formed in the Early Yanshan age. This paper demonstrates the existence of late hydrocarbon generation in the area based on the two respects of maturity alternation and decken/overturned sections. However, there are some differences in hydrocarbon generation between different sections and between different strata of the same section. The burial history study reveals that，there are mainly four types of burial evolution processes in the area, i.e., continuous deep burial, deep burial\|denudation &; planation, deep burial\|uplift\|deep burial, and deep burial\|uplift\|shallow burial, of which the former two types are of great significance to late hydrocarbon generation. The hydrocarbon generation history and the calculated results of late hydrocarbon generation potential further indicates that the late hydrocarbon generation potential of Neopaleozoic source beds is slightly higher in Dangyang area than in Chenhu area, and the hydrocarbon generation intensities both meet the standard for the formation of middle\|and small\|sized oil/gas fields. 