Abstract:When perturbed model is described with Gabor frames,the scatter waves can be calculated with Gaussian beam in the frequency domain or Gaussian packet in the time domain.For this case the precondition is that signals of the incident background wave-field should be short-duration in the time domain and broad-band in the frequency domain.With the above-mentioned modeling method an effective scatterer imaging algorithm is put forward.A common-shot-gather is decomposed with characteristic Gaussian packet firstly.All of the Gaussian packets that describe the common-shot-gather are back-propagated and projected into the model domain independently.The final scatterer is obtained by integrating all of the Gabor-scatterers that projected from Gaussian packets.One of the scatterer imaging method's key points is how to project Gaussian packet into the model domain.The scatterer imaging method is composed by 3 parts of the imaging algorithm,the projection theory from a Gaussian packet to a Gabor-scatterer,and the back-propagation scheme of Gaussian packet.The proposed scatterer imaging method gives the image that has the dimension in the model domain.Gaussian packet shares higher efficiency and better flexibility compared with wave equation.The accuracy of the proposed scatterer inversion method is tested and analyzed with a single Gabor-scatterer model in the numerical experiment.The scatterer inversion scheme is also applied in synthetic models and promising results is presented.Both of the experiments show that the proposed method shares high efficiency,and the algorithm is suitable for general models.
李辉, 殷俊锋, 王华忠, 刘守伟, 刘太臣. 高斯波包散射体成像方法[J]. 石油地球物理勘探, 2017, 52(2): 273-282.
Li Hui, Yin Junfeng, Wang Huazhong, Liu Shouwei, Liu Taichen. A scatterer imaging method based on Gaussian packet. OGP, 2017, 52(2): 273-282.
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