S U M M A R YClaerbout's daylight imaging concept is generalized to a theory of interferometric seismic imaging (II). Interferometric seismic imaging is defined to be any algorithm that inverts correlated seismic data for the reflectivity or source distribution. As examples, we show that II can image reflectivity distributions by migrating ghost reflections in passive seismic data and generalizes the receiver-function imaging method used by seismologists. Interferometric seismic imaging can also migrate free-surface multiples in common depth point (CDP) data and image source distributions from passive seismic data. Both synthetic and field data examples are used to illustrate the different possibilities of II. The key advantage of II is that it can image source locations or reflectivity distributions from passive seismic data where the source position or wavelet is unknown. In some cases it can mitigate defocusing errors as a result of statics or an incorrect migration velocity. The main drawback with II is that severe migration artefacts can be created by partial focusing of virtual multiples.

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SUMMARY The crustal structure beneath Ross Island and the Transantarctic Mountains (TAM) in Southern Victoria Land, Antarctica, is inferred using non‐linear inversion of receiver functions, derived from teleseismic earthquake data. Intermediate‐period waveforms from more than 160 teleseismic earthquakes recorded between January 1994 and January 2000 were used in the analysis. The inversion results confirm a crustal thickness of 19–21 km beneath Ross Island, consistent with previous multichannel seismic work. In addition we observe a crustal thickness of 18–20 km beneath the Ross Sea coastline immediately adjacent to the TAM. Further inland, beneath the TAM, the estimated Moho depths range from 30–33 km (∼30 km from the coast) to 36–40 km (∼85 km from the coast), deepening away from the coast beneath the TAM. These results are in broad agreement with previous seismic and gravity interpretations. Beneath the TAM a sharp mid‐crustal discontinuity is present at 8–14 km depth beneath the eastern‐most stations, but absent on the western side of the TAM, indicating a spatial change in the mid‐crustal composition.

Reflectivity images of the earth are calculated by migrating discrete grids of seismic traces. Typically, such traces are spatially undersampled on a recording grid with limited aperture width and so give rise to migration noise sometimes referred to as the acquisition footprint. For poststack migration images, we show how to partly deconvolve the acquisition footprint by applying a deblurring filter to the migration section, where the filter is the approximate inverse to the migration Green’s function. Results with synthetic and field data show that post‐stack migration deconvolution can noticeably improve the spatial resolution of migration images, decrease the strength of migration artifacts, and improve the quality of the migration image. We conclude that migration deconvolution can be a viable alternative to some of the other postmigration processing procedures based on statistics and ad hoc parameter choices.

Prestack migration deconvolution (MD) is applied to 2-D and 3-D depth migrated images computed from synthetic models and field data. The results show that prestack MD improves resolution and reduces migration artifacts. Subdividing the migration image and using multi-reference migration Green's function accounts for lateral velocity variations and attenuates some far-field artifacts.