A computer implemented method of exploration for hydrocarbons within a predetermined volume of the earth containing structural and stratigraphic features conducive to the generation, migration, accumulation, or presence of said, hydrocarbons, comprising the steps of: (a) accessing a digital representation of a VSP survey that images at least a portion of said predetermined volume of the earth; (b) selecting a shot gather from said digital representation of said VSP survey, wherein said shot gather comprises a plurality of seismic traces recorded by a receiver positioned at a depth, and corresponding to a plurality of shots with the same receiver positioned at the same depth, and wherein said shot gather also comprises a plurality of seismic traces recorded by different receivers positioned at the same depth, and corresponding to a plurality of shots with different receivers positioned at the same depth, said plurality of seismic traces together containing at least a representation of a receiver wave field and a representation of a source wave field; (c) selecting a salt flood model; (d) using said salt flood model to downward continue said representation of said receiver wave field over a plurality of down going depths, said plurality of down going depths extending at least from a depth proximate a surface of the earth to a depth at least approximately equal to said receiver depth, said downward continuation producing at least one receiver wave field estimate at each of said plurality of down going depths; (e) selecting a sediment flood model; (f) using said sediment flood model to upward continue said source wave field over a plurality of up going depths, said plurality of up going depths extending at least from proximate to said same receiver depth to proximate to the surface, thereby creating a source wave field estimate at each of said plurality of up going depths; (g) selecting one of said plurality of down going depths and said receiver wave field estimate associated therewith; (h) selecting one of said plurality of up going depths substantially equal to said selected down going depth, thereby selecting a source wave field estimate associated therewith; (i) performing an imaging condition calculation using said selected receiver wave field estimate and said selected source wave field estimate, thereby producing an imaged data set; (j) performing at least steps (g) through (i) a plurality of times, thereby producing a plurality of imaged data sets; (k) accumulating said plurality of imaged data sets, thereby obtaining an image representative of at least a portion of said predetermined portion of the earth; and, (l) using said image representative of at least a portion of said predetermined portion of the earth to explore for hydrocarbons within said predetermined volume of the earth. (a) accessing a digital representation of a VSP survey that images at least a portion of said predetermined volume of the earth; (b) selecting a shot gather from said digital representation of said VSP survey, wherein said shot gather comprises a plurality of seismic traces recorded by a receiver positioned at a depth, and corresponding to a plurality of shots with the same receiver positioned at the same depth, and wherein said shot gather also comprises a plurality of seismic traces recorded by different receivers positioned at the same depth, and corresponding to a plurality of shots with different receivers positioned at the same depth, said plurality of seismic traces together containing at least a representation of a receiver wave field and a representation of a source wave field; (c) selecting a salt flood model; (d) using said salt flood model to downward continue said representation of said receiver wave field over a plurality of down going depths, said plurality of down going depths extending at least from a depth proximate a surface of the earth to a depth at least approximately equal to said receiver depth, said downward continuation producing at least one receiver wave field estimate at each of said plurality of down going depths; (e) selecting a sediment flood model; (f) using said sediment flood model to upward continue said source wave field over a plurality of up going depths, said plurality of up going depths extending at least from proximate to said same receiver depth to proximate to the surface, thereby creating a source wave field estimate at each of said plurality of up going depths; (g) selecting one of said plurality of down going depths and said receiver wave field estimate associated therewith; (h) selecting one of said plurality of up going depths substantially equal to said selected down going depth, thereby selecting a source wave field estimate associated therewith; (i) performing an imaging condition calculation using said selected receiver wave field estimate and said selected source wave field estimate, thereby producing an imaged data set; (j) performing at least steps (g) through (i) a plurality of times, thereby producing a plurality of imaged data sets; (k) accumulating said plurality of imaged data sets, thereby obtaining an image representative of at least a portion of said predetermined portion of the earth; and, (l) using said image representative of at least a portion of said predetermined portion of the earth to explore for hydrocarbons within said predetermined volume of the earth.