大庆朝阳沟油田水淹层解释评价方法研究

大庆外围朝阳沟油田属低渗透岩性、岩性-构造油藏,由于受岩性、沉积微相、微构造及断层等因素的控制,油水关系较为复杂,注水开发后层内水淹机理及水洗状况更加复杂,水淹层解释较为困难。根据朝阳沟油田已投产井井壁取心分析资料及密闭取心井分析资料,主要通过岩石热解分析、饱和烃气相色谱分析、荧光显微图像分析等录井新技术,建立了有效孔隙度与剩余油饱和度评价图版、不同水洗程度饱和烃气相色谱判别标准、有效孔隙度和饱和烃总面积图版、Pr/nC17与∑nC21-/∑nC22+关系图版、不同水洗程度荧光图像判别标准等适合于低渗透油层的水淹解释评价方法。将这些解释评价方法应用于朝阳沟油田加密区块,共解释47口井389层:未淹油层解释235层,符合率为91.0%;低水淹层解释102层,符合率为83.3%;中水淹层解释52层,符合率为75.0%。

Research on Interpretation and Evaluation Method for Water Flooded Zones in Chaoyanggou Oilfield of Daqing

Chaoyanggou oilfield in Daqing is the low permeability lithological and lithologic-structural reservoirs.Controlled by lithology,sedimentary microfacies,microstructure and fault,oil-water relationship is complex and intraformational water flooded mechanism and water flushed situation is more complicated after water flooding development.It will be more difficult to interpret the water flooded zones.Based on the sidewall coring data of the producing wells and sealing coring well data in Chaoyanggou oilfield,new technologies of mud logging,analysis on rock pyrolysis,saturated hydrocarbon gas chromatography,fluorescence micro-image and so on,are applied.And then interpretation and evaluation methods for watered out fit for the low permeability oil-bearing formations are established ：evaluation chart between effective porosity and remaining oil saturation,criterion of gas chromatography for saturated hydrocarbon with various water flooded degree,chart between effective porosity and total area of saturated hydrocarbon,chart of the relationship between Pr/nC17and∑nC21-/∑nC22＋and criterion of fluorescence micro-image with various waterflooded degree.These methods are applied to infill blocks in Chaoyanggou oilfield.Forty seven wells and 389 layers are interpreted.There are235 interpreted non-water flooded oil formations with 91.0% of the coincidence rate.There are 102 interpreted low-water flooded oil formations with 83.3% of the coincidence rate.There are 52 interpreted middle-water flooded oil formations with 75.0% of the coincidence rate.