Nonstretching normal moveout correction via an extrapolated interferometry method

Abstract

Normal moveout correction is an essential part of seismic data processing. The accuracy of the result of traditional normal moveout correction methods depends largely on the accuracy of the picked normal moveout correction velocity, which has severe stretching at shallow layers and far-offset distances. However, the problem is usually solved by “mute,” leading to a low stacking number at far offset and a short illumination aperture for exploration. Therefore, a non-stretching normal moveout correction method based on extrapolation interferometry is proposed in this paper. While solving the problem of stretching, it further increases the effective extension length of seismic exploration and improves the coverage number of far-offset reflection points through the conversion between primary and multiple waves. Meanwhile, the introduction of high-order accumulation improves the application range of the method and overcomes the influence of coherent Gaussian noise. In this paper, the method is tested on synthetic data with different noise and applied to two field data. These applications in different data show that the proposed method is a purely data-driven method. The proposed method in this paper does not depend on the accuracy of the velocity picking. It not only achieves non-stretching moveout correction, but also effectively suppresses the effects of random and coherent Gaussian noise.