Estimation of stratigraphic heterogeneity using seismic reflection data.

The traditional approach in seismic imaging assumes homogeneous layers with constant seismic velocities. In the real earth, layers have numerous small -scale variations of properties (e.g., the seismic P-wave velocity) which a re so irregularly distributed, that they can no longer be described by dete rministic models; statistical approaches have to be used instead. These var iations can only be described by their stochastic properties. In this paper , every distinctive layer is described by its mean velocity, its variance, and a spatial autocorrelation function. This velocity model is transformed into a model for the autocorrelation of the corresponding impulse response. The parameters for this model are then estimated in the least-squares sens e using stacked and migrated seismic sections as input. The method is valid ated with synthetic data, and then applied to a real seismic data set where additional borehole data is used to verify the estimation.