The attenuation of prestack internal multiples based on virtual seismic events is computationally costly and hinders seismic data processing. We propose a multiples attenuation method for poststack seismic data by app...The attenuation of prestack internal multiples based on virtual seismic events is computationally costly and hinders seismic data processing. We propose a multiples attenuation method for poststack seismic data by approximating conventional virtual events. The proposed method is iterative. The proposed method is tested using 2D synthetic and the field poststack seismic datasets. Compared with the conventional virtual events method, the proposed method does not require data regularization and offers higher computation efficiency. The method requires to know the travel time of the primary reflection waves. The results of the application to 2D field datasets suggest that the proposed method attenuates the internal multiples while highlighting the deep primaries.展开更多
Early warning of gas in deepwater drilling risers is critical to the timely detection of seepage and consequently blowout reduction. We numerically simulate the acoustic fi eld in water-based drilling fl uids from a s...Early warning of gas in deepwater drilling risers is critical to the timely detection of seepage and consequently blowout reduction. We numerically simulate the acoustic fi eld in water-based drilling fl uids from a sound source outside the riser by using a 3D cylindrical coordinates finite-difference method. By changing the gas content of the drilling fluid, the relation between the amplitude and attenuation of the A0- and the S0-mode Lamb waves in the riser, the fl uid properties in the pipe, and the position of the top and bottom interfaces of the slug fl ow were assessed. The simulation results suggests that the amplitude and attenuation of the Lamb waves refl ect the gas content in the riser and are sensitive to low gas content. Moreover, the Lamb waves amplitude and attenuation reflect the position of the top and bottom interface of the slug fl ow.展开更多
基金supported by the National Natural Science Foundation of China(No.41674122)National Science and Technology Major Project of China(No.2016ZX05004003)National Basic Research Program of China(No.2013CB228602)
文摘The attenuation of prestack internal multiples based on virtual seismic events is computationally costly and hinders seismic data processing. We propose a multiples attenuation method for poststack seismic data by approximating conventional virtual events. The proposed method is iterative. The proposed method is tested using 2D synthetic and the field poststack seismic datasets. Compared with the conventional virtual events method, the proposed method does not require data regularization and offers higher computation efficiency. The method requires to know the travel time of the primary reflection waves. The results of the application to 2D field datasets suggest that the proposed method attenuates the internal multiples while highlighting the deep primaries.
基金partially supported by the National Science and Technology Major Project(No.2016ZX05003-004)
文摘Early warning of gas in deepwater drilling risers is critical to the timely detection of seepage and consequently blowout reduction. We numerically simulate the acoustic fi eld in water-based drilling fl uids from a sound source outside the riser by using a 3D cylindrical coordinates finite-difference method. By changing the gas content of the drilling fluid, the relation between the amplitude and attenuation of the A0- and the S0-mode Lamb waves in the riser, the fl uid properties in the pipe, and the position of the top and bottom interfaces of the slug fl ow were assessed. The simulation results suggests that the amplitude and attenuation of the Lamb waves refl ect the gas content in the riser and are sensitive to low gas content. Moreover, the Lamb waves amplitude and attenuation reflect the position of the top and bottom interface of the slug fl ow.
