Trigonal meshes in diffraction tomography with optimum regularization: an application forcarbon sequestration monitoring

Santos, E.T.F., Harris, J.M., Bassrei, A. and Costa, J.C., 2009. Trigonal meshes in diffraction tomography with optimum regularization: an application for carbon sequestration monitoring. Journal of Seismic Exploration, 18: 135-156. Diffraction tomography is an inversion technique that provides the reconstruction of a subsurface velocity field from scattered acoustic field data. High-resolution imaging conventionally requires estimation of a large number of parameters. A trigonal mesh is applied in the study described in this paper, in order to strongly reduce the number of parameters. Thus, instead of a velocity-estimate for each cell in a regular grid, the velocity is estimated only at triangle vertices, which act as control points for the interpolation of velocity field within each triangle. Regularization is required to avoid sharp artifacts due to trigonal elements. A synthetic model is adopted to test the feasibility of the proposed method for reservoir monitoring.
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