古油层识别技术及其在石油勘探中的应用(为庆祝克拉玛依油田勘探开发50周年而作)

古油层识别技术主要分为三方面：一是高孔隙度和渗透率层段识别,二是残留烃数量分析,三是盆地流体历史模拟技术.含油包裹体颗粒指数和荧光颗粒定量技术分别采用显微岩石学和激光扫描分析方法,确定储集层中油包裹体的丰度,而储集层中油包裹体丰度反映它在地质历史中古含油饱和度.油层的含油包裹体颗粒指数值大于5%,并至少有一部分样品大于10%,水层的含油包裹体颗粒指数值小于1%.一些油层中含油包裹体颗粒指数高值缺乏指示了快速成藏或浅部成藏.在石油运移通道层段,含油包裹体颗粒指数值主体值为1%～5%,但这些层段在垂向上仅局部分布.含油包裹体颗粒指数和荧光颗粒定量技术可用于识别古油层,判识古油水界面,寻找再运移石油,确定天然气或凝析气藏早期是否存在早期石油充注事件,识别次生油藏,寻找下伏油藏,限定油气充注模式.

Paleo-Oil Leg Recognition and Its Application to Petroleum Exploration

The technologies to detect paleo-oil leg include three parts: 1) recognition of zones with high porosity and high permeability, 2) analysis of residual hydrocarbons, and 3) history match for basinal fluids. The grain index and quantitative fluorescence gain rely on the micro-petrography and laser scanning analysis to determine the abundance of oil inclusion in reservoir, which characterizes paleo-oil satu- ration. The grain index of oil zone is generally over 5%, but higher than 10% for some samples at least. The grain index of aquifer is nor- mally lower than 1%. Some samples from oil zone are lack of high value of grain index (higher than 5%), which indicates rapid petroleum accumulation or shallower accumulation. In pathways of petroleum migration, the grain index mainly ranges from 1% to 5%, but they are locally distributed vertically. It is concluded that the grain index of oil inclusion and quantitative grain fluorescence technologies can be ap- plied to recognize paleo-oil leg, delineate paleo-oil and water contact, trace re-migrated petroleum, confirm oil charge event before gas or con- densate gas accumulation, find out secondary reservoir and underlying reservoir, and allow the charge history to be accurately constrained.