oa The Discover Way towards More Realistic Enhanced Resolution Seismic inversion – A Field Test

Optimum seismic inversion requires that the input data have the broadest possible frequency bandwidth coverage. Normal seismic data generally lack the low frequencies, and these are then usually augmented by low frequency models derived through various forms of spatial Well log interpolation. However, the low frequency models do not sufficiently represent in detail localized geological variations. In the pursuit to acquire broader bandwidth seismic data, Hill & Bacon, 2006 [a] wrote about the Over/Under acquisition and processing technology, following which, Özdemir et al, 2008 [b] described the optimized deghosting of Over/Under lowed streamer data in the presence of noise. Krach et al, 2010 [c] further elaborated on the technique for improved resolution and deep imaging. The DISCover method is a new modified Over-Under technique in seismic acquisition to yield a seismic dataset that is richer in the low frequencies without loss of high frequent content. These seismic spatially-sampled low frequencies do carry important smaller scale geological variations within the subsurface, and together with a minor contribution of the ultra-low frequencies from the Well log data, greatly improve the seismic inversion results. The Field test was conducted at the NW Shelf of Australia (Fig 1). The DISCover operation technique is discussed. The seismic data from the DISCover method is compared with that from a conventional survey technique (Fig. 2A and 2B). The implication for seismic inversion is demonstrated, with results for a more consistent pay geobody extraction made possible by using the DISCover dataset (Fig. 3).