Pressure and Velocity Fields Retrieval Based on a New Normalization Option and 1D Model-Free Primaries Retrieval from Marine Data

Abstract

The Marchenko method is being developed to compute redatuming operators from the reflection response based on a new normalization option at the data level. These operators can be used to retrieve the two-way focusing functions in terms of pressure and velocity, respectively, without effects from the ghost, and free-surface and internal multiples. To compute these operators an estimate of the first arrival of the redatuming operator is required. This can be done using the same model as is used for traditional migration. We then propose to delay the need for such a model and remove free-surface and internal multiples in one step while retaining the primary reflections at the original two-way traveltime. We modify the amplitude by removing the transmission effects at both sides of the equations. The resulting data becomes full focusing functions in terms of pressure and velocity at two-way traveltime, respectively. New datasets can then be generated by picking the value at each focusing level and storing it which are free of the ghost effects, free surface and internal multiples.