砂泥互层地层断裂带结构特征对断层边部剩余油控制作用

The eastern part of our country main continental oilfield has entered late high water cut stage, which affected by the segmentation of fault accounts for about 1/3, remaining oil research for fault block oilfield fault boundary past never consider the bunch of water, the spill oil, injection-production imbalances and casing damage of well pattern and other accidents caused by fault zone internal structure. The topic chosen Daqing Xingbei oilfield Putaohua reservoir for target, according to the first fault system coring wells in our country(Xing7-20-Xie632 well),through field outcrops dissection and sand box physical simulation, making clear of fault zone macrostructure, and then carrying out 3D seismic fine interpretation, using “transition displacement/ separation” and "three graph one strip" technology, establishing fault interpretation quality correction methods, confirming the fault combination patterns and connection state, combining continuous systematic coring observation description, logging curve recognition, rock thin section analysis and CT scanning 3D imaging, multi-scale quantitative characterization of sandstone-mudstone interbed fault zone internal structure of geological model and establish comprehensive chart of the response to identify core and logging curve. On the basis studying of fault zone structural feature, analysis of fault sealing mechanism and stability mechanism, and establish the corresponding quantitative evaluation method, eventually establish quantitative prediction method of remaining oil distribution at the fault boundary and safety waterflood exploitation model,this study has important scientific significance to fault block oilfield production stable and efficient development.

我国东部陆上主力油田已经进入高含水开发后期，其中受断层分割影响的断块油田约占1/3，以往针对断块油田断层边部剩余油研究从未考虑断裂带内部结构造成的串水、漏油、注采失衡和井网套损等事故。本课题选取大庆杏北油田葡萄花油层为靶区，依托我国首口过断裂带系统取心井（杏7-20-斜632井），通过露头区描述解剖和砂箱物理模拟明确断裂带宏观结构，进而开展三维地震精细解释，利用“转换位移/离距”和“三图一剥”技术，建立断层解释质量校正方法，确认断层组合模式及连接状态，结合系统取心井观察描述、测井曲线识别、岩石薄片鉴定和CT扫描三维成像，多尺度定量表征砂泥互层地层断裂带内部结构地质模型及岩心-测井曲线综合响应识别图版，在断裂带结构特征研究基础上剖析断层封闭机理和稳定机理，并建立相应定量评价方法，最终建立断层边部剩余油分布规律定量预测方法和安全注水开采模型，其研究对断块油田增储稳产和高效开发具有重要科学意义。

针对中国东部陆上主力油田高含水期断层边部注采不完善、串水漏油、井网套损和剩余油分布复杂的科学问题，结合“断层解释质量校正缺少有效方法、断裂带内部结构特征定量表征及其对断层边部剩余油控制作用研究相当薄弱、断层稳定性及其对断层边部剩余油安全注水开采研究较弱”等技术难点，以大庆杏北油田葡萄花油层为靶区，依托中国首口过断裂带系统取心井（杏7-20-斜632井），采用露头区解剖、砂箱物理模拟、测井曲线识别、岩心观察描述和岩石薄片鉴定等手段，首先对砂泥互层地层的断层组合模式及连接状态、断裂带结构特征、断层封闭性和稳定性开展研究，并分析其对断层边部剩余油的控制作用，最终建立了断层宏观组合模式、断层解释质量校正技术和断裂带内部结构地质模型，总结了断层不同组合模式和连接状态对断层边部剩余油控制作用，剖析了断层破碎带对其边部剩余油微观赋存状态控制作用，形成了断层封闭性及稳定性定量评价方法。本项目首次基于断层分段生长机理建立砂泥互层地层断层解释质量校正方法，首次基于过断裂带系统取心井资料系统研究断裂带内部结构特征，并初步探索了断层边部剩余油安全注水开采模型，其成果对断块油田高含水期增储稳产、安全高效注水开发和剩余油挖潜有重要理论意义与科学价值。