1. A method for estimating the reflection sequence of the earth from a seismic reflection trace generated by a swept frequency vibrator, including the steps of: forming an initial estimate of the reflection sequence from a model of the earth; forming an estimated seismic reflection trace from the initial estimate of the reflection sequence from the model of the earth by convolving the initial estimate of the reflection sequence of the earth with a pilot signal of the swept frequency vibrator; generating an error signal representative of the difference between an uncorrelated seismic reflection trace and the initial estimated seismic reflection trace; and revising the estimate of the reflection sequence of the earth by minimizing the error signal.