应用傅里叶尺度变换提高地震资料分辨率

针对叠后地震资料,本文提出利用傅里叶尺度变换进行提高分辨率的处理方法。由傅里叶尺度变换的性质可知,地震子波在时间域的压缩等于在频率域内频谱向高频端移动,反之亦然。因此,可利用傅里叶尺度变换性质对估算出的地震子波进行变换,得到更高频率的地震子波,再利用反演得到的滤波因子实现对地震资料的提高分辨率处理。该方法假设地震资料的反射系数序列是含白噪随机序列,地震子波具有零相位特性,且根据地震数据的信噪比估算合适尺度变换因子,再做拓频处理。模型数据测试和实际资料应用的结果均证实本文方法可有效提高地震资料分辨率,尤其适用于薄互层类储层的反演和预测,是一种简便实用的高分辨率地震数据处理方法。

Seismic resolution enhancement based on the scale characteristics of Fourier transform

We propose in this paper a simplified inversion method to enhance stacked seismic data resolution based on the scale characteristic of Fourier transform. According to the scale characteristics of Fourier transform, when seismic wavelet is compressed in the time domain its amplitude spectrum moves to high frequency band, and vice versa. First we transform estimated seismic wavelet to a wavelet with higher frequency. Then we use an obtained filter by inversion with seismic wavelet to the original seismic trace to improve the resolution. In this method, we only consider that seismic reflectivity series is of white noise and seismic wavelet is of zero phase. The scale factor can be estimated based on the signal-to-noise ratio of real seismic data before the transform. Synthetic and field data test results show that this simple method can obtain high-resolution seismic and is suitable for interbed reservoir prediction.