陆地地震勘探随机噪声统计特性

Statistical features of the random noise in land seismic prospecting

在地震勘探随机噪声压制领域,噪声通常被假设为平稳、高斯随机过程的信息.然而,在某些情况下,这样的假设并不准确.本文应用现代统计检验方法对地震勘探随机噪声的平稳性、高斯性和线性进行了研究.结果表明地震勘探随机噪声并不是传统意义上认为的平稳随机过程,其平稳性受到噪声时长和采集环境复杂程度的影响.发现噪声时间越长,采集环境越复杂,随机噪声的平稳性越差,但是对于短时长随机噪声而言,其可以近似认为是平稳的.同时,采集环境的复杂程度也影响着随机噪声的高斯性和线性特性,环境条件越复杂,随机噪声高斯性越好,线性特性越差,但总的来说随机噪声可以归为线性非高斯随机过程.

In denoising of seismic prospecting, random noise is often assumed to be stationary and Gaussian. However, this is not always appropriate for real seismic data. Here, we use the modern statistical testing methods to investigate the properties of land-seismic-prospecting random noise in the stationarity, Gaussianity and linearity. The results show that the random noise is not strictly stationary as suggested traditionally. The time length and acquisition environment can pose effects on the stationarity of the random noise. Such stationarity becomes poorer with increasing length of the noise and complexity of the acquisition environment, whereas only the noise of short length can be approximately considered as a stationary process. The results also indicate that the complexity of the acquisition environment has influence on the Gaussianity and linearity of the random noise. The complex environmental conditions always result in well Gaussianity and poor linearity of the random noise. In general, the random noise should be attributed to a linear non-Gaussian stochastic process.