Paper Summary
This paper discusses imaging using the wavefield separated into upgoing and downgoing components and including primaries and multiples. We image the reflectivity by solving Fredholm integral equations at every depth level of the image, after extrapolating the wavefields with a oneway wave equation propagator. The reflectivity, or reflected wavefield in the hypothetical experiment with point sources and receivers at the image level, is determined free of multiple scattering from the overburden. We also show how the reflectivity, obtained by inverting the matrix form of the Fredholm integral equations, can be extended to angle-dependent reflectivity at the image point.