南海东部海相砂岩油藏开发井网适应性定量评价

Quantitative evaluation of well pattern adaptability for marinesandstone reservoirs in the eastern South China Sea

针对南海东部海相砂岩油藏开发井网的适应性问题,从加密潜力、井网干扰、储量动用、开发状况四个维度开展井网评价方法综合研究。基于海相砂岩极限驱油效率校正谢尔卡乔夫公式,并结合经济因素明确调整井加密界限,从技术和经济角度综合考虑明确井网加密潜力;通过分析油藏和单井水驱特征曲线,建立井网控制储量干扰度参数,评价井网干扰程度;基于物质平衡方法,建立水驱动用储量差异百分数,判断油藏储量动用程度;通过平均采油速度、采油速度极大值、油藏采出程度等三个指标,建立开采效果分类评价标准。综合分析四类评价指标,明确当不利指标多于2项时定义油藏井网不适应,当有利指标多于2项时定义油藏井网适应。通过对典型油藏开发井网开展定量评价分析,验证了该方法可以快速高效评价油藏开发井网,也为同类油藏井网适应性分析提供参考。

To evaluate the well pattern adaptability for marine sandstone reservoirs in the eastern South China Sea,a comprehensive study is carried out from four dimensions:infilling potential,well pattern interference,reserve utilization and development status.Based on the ultimate oil displacement efficiency correction of the Cherkachov formula,the well infill boundary is clearly adjusted in combination with economic factors.The infilling potential is considered from both technical and economic perspectives.By analyzing the reservoir and single well water drive characteristic curves,the well pattern control reserve interference parameters is established for evaluating the degree of well pattern interference.By material balance method,the percentage difference in water driven reserves is established for determining the degree of reservoir reserve utilization.The classification and evaluation criteria for production effectiveness is established through three indicators:average oil recovery rate,maximum oil recovery rate and reservoir recovery degree.By analyzing four types of evaluation indicators,when there are more than two unfavorable indicators,the definition of reservoir well pattern is unsuitable,and it’s applicable when there are more than two indicators.Through quantitative evaluation and analysis on well pattern development of typical oil reservoirs,this method is able to quickly and efficiently evaluate the well pattern of oil reservoir development,and also provide reference for the adaptability analysis of similar oil reservoirs.