下扬子地区热历史与海相烃源岩二次生烃潜力

下扬子地区是中国南方海相油气勘探的优选地区，针对中、古生界海相油气勘探提出了“二次生烃，晚期成藏”的部署思路。通过盆地热史恢复获得热流史，然后正演计算烃源岩成熟度史，再利用实验模拟二次生烃量版，计算区内4套主要海相烃源岩的二次生烃强度。结果表明：(1) 下扬子地区苏北、苏南、皖南地区具有不同的热演化史；(2) 二叠系和下三叠统烃源岩具有好的二次生烃潜力(150～300 mg/g)，志留系烃源岩有一定的二次生烃潜力(约为120 mg/g)，寒武系烃源岩几乎不具有二次生烃能力；(3) 平面上，苏南、皖南地区的二次生烃条件整体上不利，苏北各凹陷区4套海相烃源岩二次生烃强度明显大于苏南和皖南地区。

Thermal History and Secondary Hydrocarbon Generation Intensity of Marine Source Rocks in Lower Yangtze Area

Lower Yangtze area is one of the prior marine blocks of petroleum exploration in South China.Aiming(at marine) petroleum exploration of Mesozoic and Paleozoic,the strategy of the secondary hydrocarbon generation(and later formation) of petroleum pool was brought forward for petroleum exploration and planning in the study area.Based on thermal history reconstruction,the thermal maturation of the marine source rocks at different geological(time is evaluated.) In addition,using secondary hydrocarbon generation model based on experiments,the secondary hydrocarbon generation intensity of the four sets of marine source rock is evaluated.The thermal history reconstruction reveals that there are obvious differences among Subei,Sunan and Wannan areas.The study of secondary(hydrocarbon) generation shows that the Upper Paleozoic and Triassic source rocks have excellent secondary hydrocarbon generation potential.Silurian source rock possesses some secondary hydrocarbon generation.Cambrian source rock,however,nearly cannot provide any secondary hydrocarbon generation.Overall,there are no advantages of(secondary) hydrocarbon generation in the southern areas of Jiangsu and Anhui.The intensity of secondary hydrocarbon generation in north Jiangsu basin is much stronger than that in the southern areas of Jiangsu and Anhui.