时频空间域振幅补偿方法及其应用

Amplitude Compensation of Time-Frequency and Space Domain: Method and Application

根据模型炮集每一频带从浅到深各时窗平均均方根振幅能量中值的变化,利用最小二乘法,推导出关于大地吸收衰减系数的线性方程组,拟合大地吸收衰减曲线,进而求得整个工区每一频带统一的振幅补偿系数,在对地震分频数据进行前述补偿系数补偿后,还要分频统计整个炮集由于近地表空间激发影响引起的振幅衰减曲线,并作空间域补偿。实际处理效果表明,时频空间域补偿与常规球面扩散、吸收补偿相比,其振幅补偿质量有明显提高。

The basie prineiple and major steps of amplitude compensation of time-frequency and space domain are presented in this paper. The key of narrow band-pass filter frequency division is how to choose band-pass filter gate with equal hand to minimize Gibbs effect and frequency leak among bands. According to the change of median of average root mean square amplitude in each time gate of model shot gathers from shallow to deep, linear equations of ground absorption and attenuation coefficients are derived to get unified amplitl,de com- pensation coefficient for each frequency band in whole area by using least square method. Except previous compensation, space domain compensation is conducted by eounting amplitude attenuation curves of shots in whole area for near-surface explosion effect in different frequency bands. Real data processing effects show that amplitude compensation in time-frequency and space domain is much better in quality than common spherical diffusion and absorption compensation method.