Illumination Effects in Rreverese Time Migration

P285 Illumination Effects in Rreverese Time Migration B. Kaelin* (3DGeo Inc.) A. Guitton (3DGeo Inc.) & F. Ortigosa (Repsol-YPF) SUMMARY In reverse time migration the imaging condition is estimated by cross-correlating the source wave-field with the receiver wave-field under the basic assumption that the source wave-field represents the downgoing wave-field and the receiver wave-field the up-going wave-field. However for large impedance contrasts and complex geological structures the wave-fields cannot be separated efficiently. In these cases the cross-correlation leads to low frequency artefacts and illumination effects. Illumination effects can be efficiently removed by dividing the cross-correlated image by the receiver illumination