基于谱分析的低频阴影检测技术

基于小波变换的瞬时谱分析方法，克服了传统傅立叶时频转换时的时窗问题，提高了地震资料频域内的分辨能力。通过谱分析方法的比较，介绍了瞬时谱分析方法比传统傅立叶变换的改进效果，以及利用瞬时谱分析方法在分频数据体低频部分识别富气层下方的低频阴影来综合预测储层的横向展布特征和含气性异常的检测。研究实例表明低频阴影检测技术可以作为一种储层预测和油气检测的有效辅助方法。

Detection of low-frequency shadows based on instantaneous spectral analysis

In this paper, we describe the ISA technique which avoid windowing problems of conventional Fourier transform and can enhance frequency resolution of seismic data. By comparing ISA with FFT, we show some obvious advantages of ISA. Utilizing ISA, we can estimate reservoir and detect oil-gas by identifying low-frequency shadows beneath rich gas reservoirs, Research has proved detection of lowfrequency shadows is an effective assistant means to reservoir prediction and oil-gas detection.