基于水驱油实验的饱和烃录井水淹层评价方法

Water-Flooded Zone Evaluation Method of Saturated Hydrocarbon Logging Based on Oil-Water Displacement Experiment

饱和烃录井取得的饱和烃参数资料不受地层水矿化度的影响,受储层非均质性的影响较小,可较为直观、准确地判断油层水淹程度。江苏油田G区块经多年注水开发,已进入高含水阶段,水淹层评价已成为当务之急。通过对采用该区块天然岩心制备的28块不同产水率岩心样品饱和烃录井水驱油岩心实验取得的饱和烃参数分析知:随产水率的升高,饱和烃图谱峰型整体损失由正态分布逐渐变为平头峰;饱和烃总面积参数As呈下降趋势,CPr+Ph、CPr/Cn C17参数呈上升趋势,且规律明显。在此基础上,优选出CPr/Cn C17、CPr+Ph和总面积作为该区块水淹敏感参数,利用试油及已投产井井壁取心分析资料,建立了CPr/Cn C17-总面积和CPr+Ph-总面积水淹层定性识别图版。经实际井验证,图版判定结果与试油结果相符。

Since the parameters obtained from saturated hydrocarbon mud logging technology are not affected by formation water salinity and reservoir heterogeneity, it can be more intuitive and accurate in determining watered-out degree of oil zones. G area in Jiangsu oilfieldhas stepped into a high water cut stage under years of water flood development, so the evaluation of water flooded zones has become more and more important. Based on the analysis of saturated hydrocarbon parameters of 28 core samples of different water production rate obtained from oil-water displacement experiment, the analysis shows that saturated hydrocarbon peak shapes change from normal to flat, and saturated hydrocarbon total area As decreases, and the parameters of CPr+Ph and CPr / Cn C17 increase with the increase of water production rate. Based on the experimental analysis, the parameters of CPr+Ph, CPr / Cn C17 and saturated hydrocarbon total area are selected as the sensitive parameters of water-flooded zones in G area. Then, sidewall cores of oil testing wells and brought-in wells are used to build qualitative identification charts of water flooded zones with the plot of CPr / Cn C17 versus total area and the plot of CPr+Ph versus total area. The identification charts are applied to actual well data, and the identification results are consistent with the test results.