碳酸盐岩油藏水平井生产段水淹规律研究

摘要

采用水平井注水开发碳酸盐岩油藏的过程中,裂缝的存在会导致注入水突进,引起水平生产井暴性水淹.以国外A油田B区块为例,采用数值模拟方法建立了典型模型,分析了水平井注水开发碳酸盐岩油藏时不同水淹模式下的含水变化规律:若为点状见水,当裂缝位于跟部和中部时含水变化率曲线出现三个峰值,当裂缝位于趾部时含水变化率曲线出现两个明显峰值;若为多点见水,含水变化率曲线出现的峰值数和见水点数呈正相关关系,含水变化率曲线出现的峰值数为见水点数加2,但当裂缝位于趾部时,则峰值数为见水点数加1.结合A油田的生产动态资料,将利用小波除噪方法处理生产数据得到的含水变化率曲线与水淹测井解释结果进行了对比,结果表明,数值模拟结果是正确的、可靠的,可为调剖堵水目标井的筛选及水淹段数的判别提供依据.%When carbonate reservoir is developed with horizontal wells, fractures will lead to water breakthrough and cause severe waterflooding.Using a foreign oilfield A as an example,the variation of horizontal well's water cut in different waterflooding patterns was studied using numerical simulations:in single point water breakthrough pattern,three peak values appear in water cut curve when fracture is in heel or central part of horizontal production well.Two peak values appear in the water cut curve when fracture is in toe of horizontal production well.In multi-point water breakthrough pattern,the peak value appearing in water cut curve is proportional to the number of waterflooded well segments.The peak number equals to waterflooded well segments plus 2.When fracture is located in the toe of horizontal production well, the peak number equals waterflooded well segments plus 1.With the production data of oilfield A, well log interpretation result is compared with water cut curves.The reasonable numerical simulation results provide a basis for selection of profile control, plugging well and the determination of waterflooded horizontal well segments.