基于S变换的属性组合法估算地层品质因子

Estimation of Quality Factor Q Using Combination of Statistical Frequency Attributes Based on S Transform

品质因子（Q）提取精度一般受地震子波谱与Q值估算方法的影响.为了提取稳定、合理的地层Q值,首先利用S变换提取较为准确的时变地震子波谱,然后通过属性组合局部线性拟合来估算Q值,最终得到稳定的地层Q值.该方法解决了实际资料提取的质心频率曲线存在局部振荡,Q值不稳定的问题.在准噶尔盆地东西部应用该技术后,目的层分辨率得到明显提高,带宽提高5～10 Hz.

Quality factor （Q） is an important parameter for hydrocarbon detection and reservoir characterization,which reflects the subsurface seismic wave attenuation.The accuracy of Q value estimation greatly depends on the extraction of the time-varying seismic wavelet spectrum and the Q value estimating method.S transform can be used to accurately extract the time-varying seismic wavelet spectrum,and the combination of statistical frequency attributes （CSFA） can be applied to estimate the Q value in order to get the stable Q value.By this method,the regional oscillation of centroid frequency curve from real data and Q value instability can be well solved.Application of this technology to the eastern and western Junggar basin allows the target zones＇ resolutions to be obviously improved,of which the bandwidth can be increased by 5～10 Hz.