基于SVI方法的折射波信噪比改善效果研究

REFRACTION WAVE SNR IMPROVEMENT BASED ON SVI METHOD

摘要: 折射波在地震勘探中有非常重要的作用,但由于近地表噪声等因素影响,折射波在地震记录上往往能量较弱,信噪比较低。因此,Bharadwaj、Mallinson等提出了超虚拟折射干涉法(Supervirtual refraction interferometry-SVI),用于提高折射波的信噪比。在此基础上,结合正演模拟数据和实际资料,对该方法的抗噪性以及相关叠加道数、褶积叠加道数等因素对处理效果的影响进行了研究,结果表明,对于信噪比>0.2的资料,在满足一定相关叠加道数和褶积叠加道数时,使用本方法后能使信噪比得到显著增强。

Abstract: The refraction wave plays an important role in the seismic exploration. However, the amplitude and the signal-to-noise ratio(SNR) of refraction are always low because of many factors, such as near-surface noise and attenuation. Supervirtual refraction interferometry(SVI) was proposed by Bharadwaj, Mallinson, etc (2011) to improve the SNR of refraction. In this article, some experiments were conducted to analyzing the resistance of SVI method to noise and the influence of the numbers of correlation and convolution traces on processing effect. It illustrates that for the data which contain a SNR greater than 0.2, the SNR can be improved a lot after implementing the SVI method as long as the requirement for number of correlation and convolution traces was met.