f Stretch and Squeeze - Just Keeping up Appearances?

Many well tie software packages provide facilities to stretch and squeeze the synthetic seismic reflectivity sequence in order to obtain a better fit with the seismic data in the vicinity of the well. If this stretch and squeeze is merely a cosmetic device, it cannot be regarded as a valid modelling tool. Besides obscuring the reliability of the tie, it may well side-track efforts towards genuine improvement. This paper considers some possible geophysical reasons for stretch and squeeze and how they might be validated.