长岭断陷深层储层包裹体特征与油气成藏过程

Fluid inclusion characteristics and hydrocarbon accumulation process of deep reservoirs in Changling rift, Songliao Basin

金晓辉 闫相宾 孙冬胜 李丽娜 陈霞 孙宜朴 李淑筠

Jin Xiaohui Yan Xiangbin Sun Dongsheng Li Lina Chen Xia Sun Yipu Li Shujun

成藏过程精细解剖是油气富集规律和选区评价研究的基础。通过流体包裹体的显微赋存状态描述、均一温度测定，指出烃类包裹体主要赋存在石英次生加大边和切穿加大边的微裂隙以及方解石胶结物中，均一化温度主频在130~150 ℃。成岩史与埋藏史分析表明随着烃源岩成熟度的增加，后期生成的高成熟度天然气向上运移，首先将低部位圈闭中的原油驱替到构造高部位的圈闭， 形成现今SN189井和SN183井中的油藏，邻近生烃中心的SN115井储层中残余沥青正是这期原油裂解的产物。后期形成的天然气沿断层向上运移聚集，形成SN182井的天然气藏，该井的流体包裹体以天然气为主。因此，沿断层向上倾方向，液烃包体含量越来越少，天然气包裹体含量增多，现今构造高部位为油藏，低部位为气藏，油、气同源。长岭断陷的坳陷区和斜坡区的古构造、砂岩上倾尖灭和砂岩透镜体油气藏是天然气勘探的主要方向。

Research on hydrocarbon accumulation process is the basis for studying hydrocarbon enrichment patterns and identifying favorable areas for petroleum exploration.Based on the microscopic description of fluid inclusion and analysis of homogenization temperature,hydrocarbon inclusions mainly occur in the secondary quartz overgrowth,microfractures crossing these overgrowth and calcite cement.The dominant frequency of homogeneous temperature was 130-150 ℃.The diagenetic history and burial history show that high maturity natural gas migrated upward with maturing of hydrocarbon source rock and displaced the oil accumulated in the lower traps into the higher traps,resulting in the formation of Well SN189 and Well SN183 accumulations.Residual asphalt in the Yingcheng Formation in Well SN115,which is near the hydrocarbon generation center,was the product of crude oil pyrolysis in this period.Natural gas generated during later period migrated upward along the fault and formed Well SN182 natural gas pool where the inclusions are mainly of natural gas.As a result,along the fault up-dip direction,the number of liquid hydrocarbon inclusions gradually decreases,while the number of natural gas inclusions gradually increases.Oil accumulated in the higher position,and gas accumulated in the lower parts.The oil and gas share the same hydrocarbon source.Up-dip pinchout sandstone and sandstone lens in the depression and slope area of Changling rift are the main targets for natural gas exploration.

10.11743/ogg20140504