用地震信号多项式拟合提高叠加剖面信噪比

利用信号横向相干性可以提高地震数据的信噪比。我们提出了一种在叠加剖面上对信号做多项式拟合来加强信号的方法。假设一个信号各道波形相同,那么信号的参数就可用其相位时间、振幅和公共波形来表示。此法的第一步是在信号时-空窗内用多道互相关确定信号时间多项式,此多项式决定了各道的信号相位时间;第二步用最小二乘法确定此窗口的信号振幅多项式,同时确定信号的期望波形,并对每个窗口重复以上计算,就可获得信号剖面的参数集,即每个窗口有两个多项式的系数和一个期望波形;最后一步是用获得的参数集合成信号剖面。此法大致相当于道组合,但它能自动检测信号,并且不受同相轴斜率和曲率的限制。此法已用于实际地震叠加剖面,见到了明显的效果。此法也可用于二维和三维的道内插。

Improvement of signal-to-noise ratio of stack section using polynomial fitting of seismic signals

Signal-to-noise ratio of seismic data can he raised using lateral coherency of signals.we advanced a method for enhancing the seismic signals of stack section by making polynoinial fitting of signals.Signal parameters can be represented by phase time, amplitude and common waveform on the assumption that a seismic signal has same waveforms on all traces. This method includes the following steps;2.Determine both signal amplitude polynomial in the window and expected signal waveform using least square method; Note: Same computation for each window is made to get a parameter set for the signal section, there being both coefficients of two polynomials and an expected wavetorm for each window.2. Synthesize signal section using the parameter set derived,This method is approximate to trace summation; however, it can detect signals automatically and is not limited by the slope and curvature of reflection leg, It was applied'to' rtal seismic stack section, and obvious effect was found,This method also can be used in trace-inter-polation of 2D or 3D seismic data.