Characterization of interbedded thin beds using zero-crossing-time amplitude stratal slices

We have developed a novel method to characterize thin beds using zero-crossing-time (ZCT) amplitude slices based on an interesting phenomenon we have noticed. Because of the reflection interferences and wavelet overlap, it is almost impossible to identify each thin bed from the composite response of interbedded thin beds. However, the seismic response of one thin bed does not always interfere with other thin beds at all times. At its ZCTs, a thin bed's reflection makes no contribution to the composite response. Therefore, unlike standard amplitude stratal slices, the imprint of a thin bed does not appear in its ZCT amplitude stratal slices. The latter makes the interference pattern of ZCT amplitude stratal slices different from those of other amplitude stratal slices. Based on this difference, the ZCT amplitude stratal slices of each thin bed can be identified from consecutive amplitude slices, and the thickness, depth, and lateral distribution of each thin bed, as well as the vertical spacing between them, can be estimated from their ZCTs. This interpretive method has been systematically tested with synthetic 3D data and has also been applied to field seismic data.