Data Quality Weighted Seismic Traveltime Tomography

Seismic tomography is believed to be the seismic method promising highest accuracy and reliability. Remaining uncertainties due to a non-zero residual error in fitting the traveltime data are often neglected. We present a numerical implementation of traveltime data weighting into the well-known SIRT algorithm which provides a more reliable velocity determination on one side and a data weight or uncertainty image including a residual error map on the other side. The data weighting allows the in-cooperation of individual data quality criteria to influence the inversion procedure and to allow a non-equal weighting of the traveltimes within the tomographic inversion. By choosing appropriate weighting factors the seismic velocities recovered during the inversion process are more realistic compared to results obtained using equal-weighted traveltimes. The data quality weighted inversion has been tested on different synthetic data sets. The additional information provided by the new approach along with the seismic velocity tomogram may support the geophysicists interpretation of a seismic tomogram.