Fractal Correction of Well Logging Curves
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摘要: 用测井曲线更准确地测量薄层、薄互层的实际地球物理属性, 对油层识别、解释, 尤其是对陆相油层地球物理测井处理解释一直有重要意义.给出了测井曲线测度的一种定义, 根据分形理论, 测度与度量尺度存在一种指数关系, 利用这种测度与尺度的指数关系求出(重建)了测井曲线.这种方法能反映测井曲线的局部变化结构, 一定程度上补偿了测井仪对地层滑动平均等测量误差造成的结果.利用大样钻探(ODP) Leg 12 7, 797C井的中、深感应电导率测井曲线(IDPH, IMPH)进行了试算.比较了原始测井曲线和校正后的测井曲线以及它们的功率谱曲线, 校正后的测井曲线比原始测井曲线更能部分消除邻层的影响, 并且其频谱成分更为丰富.所以, 分形校正方法提高了测井曲线分辨薄层的能力.Abstract: Accurate measurement of actual geophysical properties, with well logging curves, for thin layers and thin alternate layersisof greatimportance to the identification and interpretation of oil beds, and especially to the processing and interpretation of geophysical well logging data from the continental oil beds. In this paper, the authors present a definition of well logging measurement. The fractal theory shows an exponential relationship thatis present between measure and scale. Thisexponential relationship can be used to obtain or reconstruct well logging curves, reflecting the local variation structure of the well logging curves and amending some errors in such surveying measurements as stratigraphic sliding average caused by the well logger. This method has been tested with the intermediate- and deep-induction electrical-conductivity well-logging curves obtained from Ocean Drilling Project(ODP), Leg 127, 979C hole. The comparison between the original and corrected well logging curves and their corresponding power spectral curves indicates that the corrected well logging curves are more effective than the original well logging curves in the resolution enhancement, because the corrected well logging curveseliminate partof the interferences from their neighboring strata and contain more frequency spectral components. Therefore, the fractal corrected method can be employed to increase the resolution of the well logging curves to detect thin stratigrahic layers.
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Key words:
- fractal /
- well logging of thin layer /
- correction of well logging curve
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