Passive Interferometric Imaging for Limited Illumination Using Slowness Diagnosis and Directionally Constrained Gaussian Beam Migration Available to Purchase

With seismic interferometry, the subsurface reflection response can be retrieved from recordings of passive sources that are located relatively deep in the subsurface. The retrieved data can be used to image subsurface structures. Succesful interferometric imaging relies upon the availability of passive records from sufficient passive sources in the subsurface that illuminate the receivers from all angles. Such a condition would be difficult to meet in practical applications. Incomplete passive-source distributions would result in the retrieval of inaccurate Green’s functions containing artefacts that can disturb the interferometric imaging process. We propose an alternative imaging method for passive data based on Gaussian beams. In this method, passive gathers are cross-correlated individually. The dominant radiation direction of each virtual source in each correlated gather is estimated. The correlated gathers are imaged indivually, using an adapted migration algorithm that takes the dominant virtual source radiation direction into account. In this way, correct partial subsurface images can be constructed even from a limited number of passive sources.