多种驱替方式后储层物性及剩余油变化规律研究——以GD油田中一区Ng3单元11-检11井区为例

目前GD油田中一区Ng3单元11-检11井区经历了水驱、聚合物驱、后续水驱及非均相复合驱等多种驱替方式开发。探索多种驱替方式后的储层物性及剩余油分布变化规律对高含水期油藏进一步挖潜，特别是GD油田中一区Ng3单元的进一步稳产、增产具有重要意义。以中一区Ng3单元中11-检11井区为研究对象，综合利用密闭取芯井及开发动态资料，对注水、注聚及非均相复合驱等多种驱替方式后的油藏物性变化规律及剩余油分布进行了研究。结果表明，与聚合物驱前相比，聚合物驱后的储层非均质性得到了一定改善；对正韵律储层，聚合物驱后底部层位储层非均质性在聚合物驱后进一步增强，而其他部分层位的储层非均质性减弱；对于复合正韵律储层，分段水洗明显，各韵律段中下部水洗较强，各韵律段上部水洗弱、剩余油富集。非均相复合驱前后的储层孔隙度分布变化差异小，但非均相复合驱后储层的非均质性变强。该研究对GD油田中一区及类似油藏的开发具有重要意义。

The variation laws of reservoir physical properties and remaining oil distributions after various displacement methods with taking zhong11-Jian11 well area of Ng3 unit zhongyi block of GD oilfield as an example

Currently, the well area of Ng3 unit 11-Jian11 in the first block of GD oilfield has experienced the development of water flooding, polymer flooding, subsequent water flooding and heterogeneous composite flooding. It is of great significance to explore the physical properties of reservoirs and the distribution of remaining oil after various displacement methods to further tap the potential of reservoirs in the high water cut stage, especially to further stabilize and increase the production of Ng3 unit in the first area of GD oilfield. In this paper, taking zhong11-Jian11 well area of Ng3 unit zhongyi block as the research object, the variation law of reservoir physical property and remaining oil distribution after various flooding methods such as water injection, polymer injection and heterogeneous composite flooding were studied by comprehensive use of closed core well and development dynamic data. The results show that compared with before polymer flooding, the reservoir heterogeneity is improved and the reservoir porosity becomes larger after polymer flooding. For the positive rhythm reservoir, the heterogeneity of the bottom layer is further enhanced after polymer flooding, while the heterogeneity of the other parts of the reservoir is weakened. For the compound positive rhythm reservoir, the segmented water washing is obvious, the water washing is strong in the middle and lower part of each rhythm segment, while the water washing is weak and the remaining oil is rich in the upper part of each rhythm segment. The variation of reservoir porosity distribution before and after heterogeneous composite flooding is small, but the heterogeneity of reservoir becomes stronger after heterogeneous composite flooding. This study is of great significance to the development of the zhongyi block of GD oilfield and similar reservoirs.