Enhancing prestack seismic data by sparse radon transform and dynamic waveform matching

Abstract

Abstract In the field of complex underground geological structures and irregular topography, prestack seismic data often have a low signal-to-noise ratio (SNR), in which 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.