Including Absorption Into The Convolutional Model Of The Seismic Trace

Higher frequency seismic signals travel faster than lower frequency<br>signals. Thus it can be expected that some component of the differences<br>observed between velocities calculated from check shots (signal frequency<br>50 hz.) and sonic logs (signal frequency 12000-30000 Hz) would be due to<br>dispersive effects. In fact it has been stated (GSI 1983) that with modern<br>sonic tools most of this difference can be ascribed to dispersive<br>effects. Thus using a properly edited sonic log and calculating the<br>synthetic with accurate absorption should remove the need for check shot<br>calibration of the sonic log to obtain accurate ties to the seismic<br>section.