缝洞储集体三维电阻率测井基础研究

To accomplish the qualitative identification and quantitative evaluation of fracture-cave formation, it is necessary to study the basic theory and application method of three dimensional resistivity logging. Abstract the mathematical and physical property and establish proper model of fracture-cave; complete the accurate mesh generation by using adaptive mesh generation method, meanwhile on the basis of multi-core CPU and GPU acceleration method and pre-condition technology, the accurate and fast numerical simulation of three dimensional resistivity logging in fracture-cave formation. Study three dimensional resistivity logging response in different fracture property, cave size, infill type and various combination of fracture and cave, analyse the distribution of sensitive to fracture-cave model. Use the shrinked model to manufacture the three dimensional resistivity logging laboratory instruments; on the basis of sink model, build the downhole environment with the help of different combinationsimulation water and sink solution, then measure the laboratory response of the three dimension resistivity tool. Combine the numerical simulation and laboratory measurement, systematicly study the three dimension resistivity logging characteristics of fracture-cave formation to provide the help to the evaluation of fracture-cave reservior.

为实现缝洞型油气藏的电测井定性识别与定量评价，进行三维电阻率测井方法基础理论和应用方法研究。将缝洞储集体抽象、等效，建立合适缝洞储集体数学物理模型；采用自适应网格剖分方法实现缝洞储集体精确剖分，基于微机多核处理器与GPU细粒度并行技术以及辅助预条件子处理方法，实现复杂缝洞储集体三维电阻率测井响应快速精确数值模拟研究。研究不同裂缝产状、洞穴尺寸、填充类型、井周方位以及不同缝洞组合条件下三维电阻率测井响应特征，分析其测井响应对缝洞储集体分布敏感性。采用优化缩小模型，进行三维电阻率测井模拟实验仪研制，在水槽模型基础上，利用模拟地层和水槽溶液的不同组合方式，构建不同的井下模拟环境，进行缝洞储集体三维电阻率测井模拟测量。将实验室物理测量同数值仿真相结合，系统研究缝洞储集体三维电阻率测井响应特征，为缝洞型油气藏的测井评价提供帮助。

三维电阻率测井是解决复杂缝洞储集体及大斜度井/水平井测井评价的发展趋势和必然要求。因此开展缝洞储集体三维电阻率测井响应基础研究，具有极为重要的意义。基于缝洞储集体形态特征，进行缝、洞数学物理模型抽象;结合数值模拟，优化仪器参数，研发了缩小比例侧向仪器，建立了一套完整的实验室物理模拟系统；进而研究了侧向测井响应与缝洞地层发育规模、产状、位置和充填物电阻率等参数的相关性；最终提出了一套基于侧向测井资料对裂缝型地层进行裂缝参数实时提取、解释的方法。研究表明低角度缝侧向响应呈现负差异，而高角度缝呈现正差异;随着仪器离开洞穴或裂缝距离的增大，侧向测井视电阻率增大；不同规模的洞穴或裂缝，侧向测井响应区间也会随之发生变化；随着填充物电阻率的增大，侧向测井视电阻率略有增大。为实现储层方位信息探测，研制了方位阵列侧向测井仪器，并结合自适应有限元数值模拟和物理模拟研究方位阵列侧向仪器的三维探测能力。将数值模拟与物理模拟对比标定，研究研究了单一裂缝、过井眼洞穴和井旁洞穴的三维侧向测井响应，为缝洞储集体识别和评价提供理论依据。研究显示，新型仪器对裂缝、洞穴储层有较好的方位敏感性。