基于改进的广义S变换求取地层品质因子Q值

地层的品质因子Q值对衡量地震波传播过程中的能量衰减以及地震资料的处理、解释有重要意义。在实际生产中求取品质因子最实用的方法是频谱比法,但传统的频谱比法面临时窗选取等问题。本文利用改进的广义S变换时频特性及与傅里叶谱相联系的特性,提取地层上、下界面对应的瞬时频谱,并通过拟合振幅比与频率的关系得到地层的品质因子Q值。数值模拟及实际资料处理均证明了该方法的有效性。

Estimation of quality factor based on improved generalized S-transform

It is important to measure quality factor Q in seismic data processing and interpretation.In practice,the most commonly used estimation method of quality factor Q is the spectral ratio method.However,the window selection is always a main issue in this traditional spectral ratio method.With superior time-frequency characteristics and the Fourier spectrum of the improved generalized S-transform,we extract the corresponding instantaneous spectrum of upper and lower interfaces of formation.By fitting the relationship between frequency and amplitude ratio,we estimate finally the quality factor.Both numerical simulation and field data show the effectiveness of this method.