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Geophysical reservoir characterization in a complex geologic environment remains a challenge. Conventional amplitude inversion assumes reliable seismic amplitudes. In a complex environment, inadequate illumination of the subsurface due to complex geology or the acquisition geometry has detrimental effects on the amplitudes and phase of the migrated image. Such effects are not compensated for in conventional seismic inversion techniques. Consequently, an imprint of various nongeological effects will manifest themselves in the results of seismic inversion, leading to a less reliable estimation of the resultant acoustic and elastic parameters. The depth domain inversion workflow uses point spread functions to capture the dip-dependent illumination effects due to acquisition geometry and complex geology. The amplitude inversion is performed in the depth domain and the output is an acoustic impedance volume corrected for illumination effects. This paper presents the results of a field data example with the objective of comparing the results of the time domain inversion and the depth domain inversion, identifying and explaining both differences and similarities. This leads to an assessment of what should be expected from the depth domain inversion approach, including key advantages and limitations.

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Multisensor streamer acquisition records both pressure and acceleration in the vertical and crossline directions. It enables the reconstruction of a dealiased representation of the upgoing pressure wavefield at any location within the streamer array. This is achieved by joint reconstruction and deghosting using a generalised matching pursuit (GMP) algorithm. To achieve an independent and quantified evaluation of the reconstruction quality, recorded seismic data is compared with the reconstructed seismic data at a witness streamer location. This paper presents the concept and results of this witness streamer experiment. The results show that mitigations can significantly reduce the impact of the main assumption of the GMP algorithm, which could otherwise compromise the quality of the early-time reconstruction in shallow water. Using these techniques, the reconstruction quality compared with an independent witness streamer is consistent from the shallow part to the deeper part of the data, with a very good match between the recorded and reconstructed data.