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In the field of complex underground geological structures and irregular topography, prestack seismic data often have a low Signal-to-Noise Ratio (SNR), where weakly reflected signals are buried beneath strong incoherent, and scattered noise. Stacking, such as beamforming along the moveout surfaces of coherent local events, can significantly improve seismic data quality. Accurate and efficient estimation of the moveout for an irregular acquisition geometry and uneven illumination is important in a complex environment. In this paper, a new optimal stacking approach for enhancing weak prestack reflection signals is presented. The proposed method mainly includes regional division and moveout estimation. Optimal stacking should be implemented within local time and space domains. Based on beam ray theory, we designed a reasonable regional division of the Common-Shot (CS), Common-Receiver (CR), and Common-Middle-Point (CMP) domains. Then, we proposed using the sparse radon transform and dynamic waveform matching method to estimate the moveout surfaces of local reflection events. The sparse radon transform was applied to obtain the linear moveout to ensure the correctness of the reflection wave direction. The residual nonlinear disturbance was estimated using the dynamic waveform matching method. Tests on synthetic and field data demonstrated the effectiveness of the proposed method, which can effectively improve the SNR of prestack seismic data and attenuate incoherent noise.

Angle‐domain common‐image gathers are an important tool in the post‐processing of seismic images and for reservoir characterization. The generation of angle gathers is a very important issue when dealing with angle‐domain images. Efficiency and robustness are the main concerns in the generation of angle gathers. In this paper, we propose two methods for producing angle gathers based on the implementation of a reverse‐time migration. In the hybrid method, we adopt the local‐plane‐wave decomposition method to extract the local plane waves and obtain two possible opposite propagation directions in the time‐wavenumber domain. Then, Poynting vectors are used to determine the correct propagation direction. The hybrid method achieves a satisfactory balance between robustness and computational efficiency. Furthermore, in the improved hybrid method, additional computational acceleration is obtained by separating the overlapping and non‐overlapping wavefield areas. The hybrid method is only applied in these areas with overlapping wave fronts, and the Poynting‐vector‐based method is adopted in the other areas. The location of the overlapping events is determined using the eigenvalues of the structural tensor. Finally, the two‐dimensional synthetic and field examples demonstrate the effectiveness of both methods.