准噶尔盆地腹部非均一捕获包裹体研究

Study of Inhomogeneous Fluid Inclusion in the Hinterland of Junggar Basin

不少学者在准噶尔盆地腹部储层砂岩样品中检测到大量的明显高于样品所处地层经历的最高温度的包裹体均一温度数据。经作者研究发现，具有异常高均一温度的包裹体多为捕获自油水非均一体系的三相包裹体，显微镜下即可观察到包裹体内含有气相、液相油和液相水三相，油相在紫外光下发黄色荧光，气相和水相不发荧光，在不同井J1 s、J1 b样品中均有分布，且丰度极高，主要赋存于颗粒愈合裂隙及溶蚀成因的愈合微溶孔和颗粒次生加大边中，多与气态烃包裹体、含气态烃盐水包裹体、盐水包裹体以及纯液体包裹体等不同类型的包裹体共生，均一温度主要分布在130～200℃之间，无明显规律性。综合分析表明，这类包裹体形成于始新世-中新世时研究区内油气调整过程中迁移的油水过渡带中。根据共生的含气态烃盐水包裹体均一温度，结合埋藏史和热演化史，恢复了包裹体捕获时间，为38～17 Ma，且浅部比深部地层中包裹体形成时间较晚，代表了古油水界面到达某一深度的不同时间。

Previous studies indicate that the homogenization temperature of many fluid inclusions from the Low-er Jurassic J1 s and J1 b sandstone samples in the hinterland of Junggar Basin are much higher than the maximum temperature that the formation experienced.In this paper,it is confirmed that three-phases inclusions trapped from oil-water heterogeneous environment are predominant in the abnormal inclusions.Gas,liquid oil and liquid water can be observed in these inclusions by microscope.Oil releases yellow fluorescence while gas and water do not under the UV-light.These inclusions,rich in J1 s and J1 b of many wells,are mainly discovered in the healed cracks,corroded hollows and secondary outgrowth cementation of rock particles.And they usually asso-ciated with gaseous hydrocarbon inclusions,salt water inclusions with gaseous hydrocarbon,salt water inclusions and liquid inclusions.Their homogeneous temperatures range from 130 to 200 ℃ without obvious law.The abnormal fluid inclusions were trapped in the moved oil-water transitional zone during the secondary migration and adjustment of oil and gas in Eocene-Miocene.The trapped time of these inclusions were revealed to be about 38-17 Ma based on the homogenization temperatures of salt water inclusions and the burial and thermal histories of the samples.In addition,the trapped time become older with increase of depth and represent the time the paleo-oil-water contact reached some depth.