东营凹陷DX176块低电阻率油层评价技术

Low Resistivity Payzone Evaluation Methodology for DX176 Block in Dongying Depression

针对东营凹陷DX176块沙四段低电阻率油层的特点,提出了基于储层岩性细分和含水饱和度泥质校正的低电阻率油层测井评价方法。阐述了岩性细分的方法、岩性与低电阻率油层成因的关系。分析了泥质的特性、泥质在地层的分布形式以及地层电阻率与泥质含量的关系。对简化的西门杜模型、双水模型和混合泥质模型等3个具有泥质校正功能的含水饱和度计算模型进行研究、分析和对比,并对混合泥质含水饱和度计算模型进行改进。总结出适用于该块低电阻率油层的油、水综合评价技术。该方法在DX176块应用效果良好,测井解释符合率达到90%。

After analysing the characteristics of the low resistivity payzones in S4 section at DX176 block in Dongying depression, proposed is the low resistivity payzone well logging evaluation methodology based on subdivision of reservoir lithology and water-saturated shale correction. Stated are the method of lithology subdivision and the relationship between lithology and the gen- esis of the low resistivity payzone. Analyzed are the shale property, shale distribution forms in formation and relationship between the formation resistivity and shale content. Researches, ana- lyses and contrast are proceeded on the 3 water saturation computation models with function of shale correction, such as the simplified Simandoux model, the double-water model and the mix- ture shale model. And the mixed water-saturated shale computation model has been improved. Summarized is the oil/water layer comprehensive evaluation methodology which is fit for the low resistivity pay zones in this block. Its practical application in DX176 block is better, and the logging interpretation coincidence rate reaches 90%.