利用油包裹体丰度识别古油藏和限定成藏方式

To Identify Paleo-Oil Reservoir and to Constrain Petroleum Charging Model Using the Abundance of Oil Inclusions

储集层中残留烃类数量指示了它在地质历史中的古含油饱和度,它包括赋存于孔隙和裂隙之中的烃类和胶结物中的烃类流体包裹体,目前采用的分析技术有储层可溶烃数量和成分(抽提、TLC-FID、HPLC、ROCK-EVAL),油包裹体丰度(含油包裹体颗粒指数GOI,荧光颗粒定量QGF)、储层固体沥青数量(SBI)与流体包裹体地层学(FIS)。利用油包裹体丰度可识别古油藏,判识古油水界面(POWC),寻找再运移石油,确定天然气或凝析气藏早期是否有石油充注事件,识别次生油藏,寻找下伏油藏,限定油气充注模式。本文以塔里木盆地牙哈凝析气气藏与英南2气藏为例,展示了如何利用油包裹体丰度识别古油藏和限定成藏方式。

Paleo-oil saturation is indicated by the amount of residual hydrocarbon in porosity as free oils and in diagenetic cement as fluid inclusions. The present analytical items include the amounts and composition of soluble organic matters or residual oils （via extraction, TLC-FID, HPLC）, ROCK-EVAL, abundance of oil inclusions （Grains containing Oil Inclusion; GOI, Quantitative Grain Fluorescence, QGF）, abundance of solid bitumen （Solid Bitumen Index, SBI）, fluid inclusion stratigraphy （FIS）. GOI and QGF techniques are used to identify paleo-oil leg, to delineate the paleo-oil water contact （POWC）, to trace the remigration petroleum, and to confirm if there is oil charge event in the early stage of the gas accumulation or condensation reservoirs. GOI data is also allowed to identify the secondary oil-gas reservoirs, to find lower level oil-gas reservoirs, and to accurately constrain the charging model of oil-gas reservoirs. The case studies of the Yaha condensate field , the Yinnan 2 gas field in the Tarim basin are described to demonstrate how to actually apply the GOI method to identify paleo-oil reservoir and to constrain the charging model of oil-gas reservoirs in petroleum exploration.