谱模拟方法及其在提高地震资料分辨率中的应用

Spectrum modeling method and its application to seismic resolution improvement.

地震反褶积的最终目标是消除地震子波的影响,恢复地层反射系数序列。本文考虑到子波的空间和时间变化特性,通过一种改进的谱模拟处理,有选择地控制频率域反褶积算子,从地震记录中初步模拟出子波的振幅谱,并在频率域实现对地震记录的零相位反褶积。然后针对反射系数不总是随机白噪的特点,利用工区内现有的井资料,再次通过谱拟合方法得到与该地区沉积特点相符合的地层反射系数谱的分布特征,并对第一步的处理结果进行谱的有色补偿,从而达到提高叠后地震资料分辨率的目的。

The final goal of seismic data deconvolution is to eliminate influence resulting from seismic wavelet to recover the reflection coefficient series of formation. Spectrum modeling method is advanced, which involves the following essential points: ·With the consideration of space and time variations of wavelet, improved spectrum modeling processing is taken to have both desirable deconvolution operator and modeled amplitude spectrum to finally achieve zero phase deconvolution of seismic data in frequency domain. ·In view of the fact that reflection coefficient is not always random white noise, and with the use of existing borehole data in the prospect, spectrum fitting is done to obtain the reflection coefficient spectrum of formations that correspond to sedimentary characteristic in the prospect. ·Spectral “color compensation” to processing result in the first step is achieved to improve the resolution of poststack seismic data. Modeling and real processing results prove the method right and practical.