油气成藏门限及其研究方法

Hydrocarbon accumulation threshold and its study methods

对油气成藏模式和成藏机理进行了综合研究,提出了油气成藏门限的概念;建立了油气成藏门限的判别方程。讨论了油气成藏门限的主控因素,包括成藏体系规模、剖面上的源—储—盖层厚度比、源岩层年代或埋深、温压介质条件和构造变动次数等,介绍了油气成藏门限研究的技术原理和方法。以塔里木盆地满加尔凹陷及周缘地区为例,计算了寒武—下奥陶统源岩的生油和生气量。油气成藏门限及聚集效率。计算结果表明,生油、气量分别为1812.407×10~8t和4343.743 ×10^(11)m^3,油、气成藏门限分别为566.503×10~8t和3011.689×10^(11)m^3,油、气聚集效率分别为68.74％和30.6％。

The concept of hydrocarbon accumulation threshold (HAT) was built up on the basis of the study on pattern and mechanism of petroleum accumulation, and its discriminative equation was deduced. The key factors for controlling HAT, including scale of petroleum accumulation system,source-reservoir-cap ratio in the thicknesses on the profile, the depth or age of source rock, temperature and pressure, times of tectonic movement, were discussed. The working flow and research method for HAT were introduced. Taking the Manjiaer Depression and its around area in Tarim Basin as examples,the quantity of hydrocarbon generation,threshold and efficiency of hydrocarbon accumulation in Cambrian-lower Ordovician Formation were calculated. The calculated results show that the oil generation is 1812.4 hundred million tons and the gas generation is 4343.743 hundred billion cubic meters. The oil accumulation threshold is 566.503 hundred million tons and the accumulation threshold gas is 3011.689 hundred billion cubic meters.The efficiencies of oil and gas accumulation are 68.74 percent and 30.67percent, respectively.