Comparison of averaging methods for velocity model building from well logs

Using high frequency sonic log data, we compare velocity estimation methods that use either two or three Taylor series terms (linear and quadratic models) to estimate velocity versus depth. Then we verify which method is more accurate with respect to the phase factor of the overall propagator. The estimated traveltime parameters are computed and analysed for the log data and for each averaging model. The analysis which is illustrated on well log data from the North Sea verifies that the velocity models which preserve the traveltime parameters have better accuracy than others