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声波反射成像测井是利用阵列声波测井的反射波进行井旁构造成像的测井新方法,由于是从滑行波能量较强的阵列声波信号中来获得反射波,因此反射波的提取问题尤为重要,文中采用能使波场更加聚焦的高分辨率Radon变换来提取反射波.分析得出滑行波和反射波到时在阵列数据道情况下表现为线性或近似线性特征,因而采用线性Radon变换方法.首先分析了声反射成像测井不同数据道集的波场几何特征,得出滑行波和反射波在不同道集都表现有不同程度的视速度差异,为反射波提取提供了依据.传统的Radon变换采用的最小二乘法不能使同相轴在Radon域足够聚焦,结合最大熵原理和贝叶斯原理实现了线性高分辨率Radon变换,模型数据处理结果表明后者可以在较复杂条件下提取出期望的波场.采用高阶交错网格有限差分模拟得到软、硬地层声反射成像测井波场,处理结果表明,相对于最小二乘Radon变换,采用高分辨率Radon变换后可以使波场更加聚焦,能提取出高质量的反射波,并能适应不同性质地层,相比于目前应用较多的反射波提取方法,其结果更接近于理论波形.实际数据处理也表明了该方法的有效性和准确性.该方法在声反射成像测井的速度分析、数据道插值以及偶极反射波提取方面有一定潜力,需要进一步研究.
The acoustic reflection imaging logging is a new logging method which uses the reflected wave of the array acoustic logging to construct the image of the well. Because the reflected wave is obtained from the array acoustic wave signal with strong traveling wave energy, the problem of extracting the reflected wave is especially Important, the paper uses the high-resolution Radon transform which can make the wave field more focused to extract the reflected wave.The analysis results show that the glide wave and the reflected wave show the linear or approximate linear characteristic in the case of the array data track, so the linear Radon transform Method.Firstly, the wave field geometric characteristics of different data gathers of acoustic reflection imaging logging are analyzed, and it is concluded that the difference of apparent velocities between the gliding waves and the reflected waves in different gathers is different, which provides a basis for the extraction of reflected waves. The least square method used in Radon transform can not make the events in the Radon domain sufficiently focused. Combined with the maximum entropy principle and the Bayesian principle, a linear high-resolution Radon transform is achieved. The results of the model data processing show that the latter can be extracted under more complicated conditions The expectation of the wave field.Using high-order staggered grid finite difference simulation to obtain soft and hard formation acoustic reflection imaging logging wavefield, the results table , Compared with the least square Radon transform, the high-resolution Radon transform can make the wavefield more focused, can extract high-quality reflected waves, and can adapt to different properties of the formation, compared to the current application of more reflected wave extraction Method, and the result is closer to the theoretical waveform.The actual data processing also shows the validity and accuracy of the method.The method has certain potential in the velocity analysis of acoustic reflection imaging logging, data-channel interpolation and dipole reflection wave extraction , Needs further study.