从热演化程度分析江汉平原及周缘中古生界晚期油气勘探潜力

From the Degree of Thermal Evolution, the Exploration Potential of Oil and Gas for the Late Middle Paleozoic in and Adjacent to the Jianghan Plain Is Analyzed

摘要: 江汉平原及周缘中古生界晚期成藏对油气勘探具有重要意义。文章通过开展主要烃源岩有机质热演化程度的系统分析，及配套的主要层段的储层研究，认为早燕山期构造隆升且剥蚀幅度不大、晚燕山期–早喜山期沉降幅度较大的地区具有晚期生烃的条件，且具有较大的资源规模，是寻找油气的有利地区，提出沔阳凹陷西部、小板凹陷–岳口低凸起东部、江陵凹陷北部–荆门断陷南部为晚期成藏的有利勘探区块。同时认为，借助涪陵气田的勘探经验，开展以寒武系下统和志留系下统为目的层的非常规油气勘探工作值得期待。

Abstract: The late-phase hydrocarbon accumulations at the Middle Paleozoic age in and adjacent to the Jianghan Plain have an importance implication for hydrocarbon exploration there. In this paper, based on a systematical analysis on the organic evolution degree of the main source rocks and the study on the main reservoirs, it is believed that considerable-scale resources may occur in the areas, which is characterized by the less Early Yanshanian Uplift and erosion and great Late Yanshan-Early Himalayan subsidence, favorable for late-phase hydrocarbon generation, and that the main reservoirs occur in the Permian, so that it is the good place looking for gas and oil. It is proposed that the favorable exploration blocks in the study area may be represented by the western Mianyang De-pression, Xiaoban Depression-the east of Yuekou low-relief, the north of the Jiangling Depression-the south of the Jingmen faulted depression, which are characterized by late-phase hydrocarbon accumulations. We also think that with the help of the exploration experience in Fuling oil field, it is worth looking forward to carry out the work of unconventional oil and gas exploration with the aim stratum of Lower Cambrian Series and Lower Silurian Series.