Application of Wave Field Continuation to the Inversion of Refraction Data

Three examples of the inversion of refraction data by downward continuation illustrate the applicability of the method to field data. The first example is a refraction profile from the Mojave Desert, California. These data are spatially aliased and contain clear evidence of lateral inhomogeneity. The inversion in this case produces a broken image in the slowness-depth domain due to the lateral inhomogeneity, but a useful average velocity model is still obtained. The second example is a shallow marine reflection profile. Here, the truncation effects due to the finite horizontal aperture 'of the recording cable produce artifacts in the slowness-depth domain. The velocity model is, however, distinct from these artifacts, and the presence of strong precritical reflections aids in the inversion. The third example is another shallow marine reflection profile. The inversion of these data illustrate the utilization of constraints provided by multiples as well as primary arrivals.