Abstract:

Given the lack of quantitative evaluation methods for frac hits effects，a diagnostic analysis method was developed based on  shut-in pressure drop curve. For the zipper fracturing process of a platform well group，the shut-in pressure drop curves under four typical frac hits modes were identified and used to diagnose frac hits types. Six typical fracturing stages with frac hits of the Jimsar platform A were selected as application cases of the proposed method. The method effectiveness was verified by comparing the application results with the microseismic monitoring results. Moreover，based on the pressure drop well testing interpretation method，the typical shut-in pressure drop curves of two frac hits types in Jimsar，namely the internal frac hits within a new well group，and the  frac hits between new and old well groups，were fitted and analyzed to interpret fracture network parameters. The interpretation results showe that the internal frac hits within a new well group affects the stimulation effects of both the primary and secondary fractures，and the specific hit effects vary with the frac hits types. The frac hits between new and old well groups mainly affects the stimulation effect of primary fractures，resulting in the change of fracture networks from "long and wide" to "short and narrow". Correspondingly，the effective fracture volume is reduced by 28%，and the overall stimulation effect is degraded.

Key words:

Jimsar shale oil, platform well group, frac hits, shut-in pressure drop curve, well testing interpretation

摘要：

摘要：针对目前缺乏压裂窜扰效果定量评价方法的难题，创新提出一套基于停泵压降曲线的压裂窜扰效果诊断分析方法。结合井组拉链式压裂工艺，提出了4种典型窜扰模式下的停泵压降曲线，用以诊断压裂窜扰类型。选取吉木萨尔页岩油A平台6个典型压裂窜扰段开展实例应用，通过与微地震监测结果对比，验证了方法的有效性。在此基础上，利用压降试井解释方法对吉木萨尔“新井组内部压窜”和“新老井间压窜”两种典型的停泵压降曲线开展拟合分析，反演解释缝网参数。解释结果表明，新井组内部压窜使主次裂缝的改造效果均受到影响，具体影响效果因窜扰类型的不同而存在差异；新老井间压窜主要影响主裂缝的改造效果，导致缝网由“长宽”向“短窄”转变，有效体积降低28%，整体改造效果变差。

关键词:

吉木萨尔页岩油, 平台井组, 压裂窜扰, 停泵压降曲线, 试井解释