AGI Training Module, Thin-Bed Interpretation

The thin-bed regime starts when the one-way traveltime thickness of the wedge is one-fourth the dominant wavelength of the illuminating wavelet (or when the two-way traveltime is one-half the dominant wavelength) and then extends across the thinner portion of the wedge. The wedge-model animation shows that the magnitude of the reflection amplitude decreases and that the time difference between the reflections from the top and base of the bed stays constant as the bed thickness continues to decrease to smaller values. The key distinctions between the seismic reflection process for thick beds and thin beds are summarized in the following table.