Constraints on Minimum Velocity Variance for Seismic Traveltime Tomography
نویسندگان
چکیده
SUMMARY Traveltime data together with known spacing between sources and receivers for seismic transmission tomography can be used to determine rigorous constraints on the minimum and maximum wave speeds in the propagating medium. These constraints lead to a new minimum variance criterion on inversion algorithms. These results do not improve the velocity reconstructions directly , but provide rigorous and easily computed gures of merit to help evaluate the diiculty of the reconstruction problem and the performance of tomographic inversion codes. Speciically, these criteria may be used during preprocessing to decide whether linear or nonlinear traveltime tomography methods are required for analyzing a given data set, or during postprocessing to determine whether regularization methods used to constrain the maximum model variance were overly restrictive.
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