To make the quantitative results of nuclear magnetic resonance(NMR) transverse relaxation(T;) spectrums reflect the type and pore structure of reservoir more directly, an unsupervised clustering method was developed t...To make the quantitative results of nuclear magnetic resonance(NMR) transverse relaxation(T;) spectrums reflect the type and pore structure of reservoir more directly, an unsupervised clustering method was developed to obtain the quantitative pore structure information from the NMR T;spectrums based on the Gaussian mixture model(GMM). Firstly, We conducted the principal component analysis on T;spectrums in order to reduce the dimension data and the dependence of the original variables. Secondly, the dimension-reduced data was fitted using the GMM probability density function, and the model parameters and optimal clustering numbers were obtained according to the expectation-maximization algorithm and the change of the Akaike information criterion. Finally, the T;spectrum features and pore structure types of different clustering groups were analyzed and compared with T;geometric mean and T;arithmetic mean. The effectiveness of the algorithm has been verified by numerical simulation and field NMR logging data. The research shows that the clustering results based on GMM method have good correlations with the shape and distribution of the T;spectrum, pore structure, and petroleum productivity, providing a new means for quantitative identification of pore structure, reservoir grading, and oil and gas productivity evaluation.展开更多
加速动态时间规整(fastDTW)算法在测井曲线相似性度量过程中存在异常点问题,且难以确定搜索边界。针对上述问题,本文首先将fastDTW算法与SDTW(summation dynamic time warping)算法结合,得到fastSDTW算法,通过重构测井曲线综合时间序列...加速动态时间规整(fastDTW)算法在测井曲线相似性度量过程中存在异常点问题,且难以确定搜索边界。针对上述问题,本文首先将fastDTW算法与SDTW(summation dynamic time warping)算法结合,得到fastSDTW算法,通过重构测井曲线综合时间序列梯度信息和数值信息解决异常点问题。然后,结合井轨迹资料提出自适应搜索边界,并基于该边界,应用fastSDTW算法进行斜井和水平井测井曲线相似性度量。结果表明,基于自适应搜索边界的fastSDTW算法的精度更高,时间复杂度为O(N),确保了算法的运行速度。最后,将该算法应用到水淹层识别工作中,通过邻井对比的方式识别水淹层,取得了预期的应用效果。展开更多
基金Supported by the National Natural Science Foundation of China (42174142)National Science and Technology Major Project (2017ZX05039-002)+2 种基金Operation Fund of China National Petroleum Corporation Logging Key Laboratory (2021DQ20210107-11)Fundamental Research Funds for Central Universities (19CX02006A)Major Science and Technology Project of China National Petroleum Corporation (ZD2019-183-006)。
文摘To make the quantitative results of nuclear magnetic resonance(NMR) transverse relaxation(T;) spectrums reflect the type and pore structure of reservoir more directly, an unsupervised clustering method was developed to obtain the quantitative pore structure information from the NMR T;spectrums based on the Gaussian mixture model(GMM). Firstly, We conducted the principal component analysis on T;spectrums in order to reduce the dimension data and the dependence of the original variables. Secondly, the dimension-reduced data was fitted using the GMM probability density function, and the model parameters and optimal clustering numbers were obtained according to the expectation-maximization algorithm and the change of the Akaike information criterion. Finally, the T;spectrum features and pore structure types of different clustering groups were analyzed and compared with T;geometric mean and T;arithmetic mean. The effectiveness of the algorithm has been verified by numerical simulation and field NMR logging data. The research shows that the clustering results based on GMM method have good correlations with the shape and distribution of the T;spectrum, pore structure, and petroleum productivity, providing a new means for quantitative identification of pore structure, reservoir grading, and oil and gas productivity evaluation.
文摘加速动态时间规整(fastDTW)算法在测井曲线相似性度量过程中存在异常点问题,且难以确定搜索边界。针对上述问题,本文首先将fastDTW算法与SDTW(summation dynamic time warping)算法结合,得到fastSDTW算法,通过重构测井曲线综合时间序列梯度信息和数值信息解决异常点问题。然后,结合井轨迹资料提出自适应搜索边界,并基于该边界,应用fastSDTW算法进行斜井和水平井测井曲线相似性度量。结果表明,基于自适应搜索边界的fastSDTW算法的精度更高,时间复杂度为O(N),确保了算法的运行速度。最后,将该算法应用到水淹层识别工作中,通过邻井对比的方式识别水淹层,取得了预期的应用效果。
