Improving pre-salt imaging through multi-layer horizon-constrained tomography – a case study in Brazil's Campos basin

Integration of broadband seismic data into reservoir characterization workflows: A case study from the Campos Basin, Brazil

“…Being rich in low-and high-frequency contents, broadband data can image deeper targets, improve vertical resolution, and ultimately reduce the uncertainty in reservoir characterization. The benefits of such an acquisition configuration have been demonstrated in previous seismic imaging (Soubaras and Whiting, 2011;Masclet et al, 2015a) and seismic velocity model building work (Masclet et al, 2015b). The improvement in reservoir characterization conditioned by the wider frequency bandwidth of broadband seismic data has also been shown in previous case studies (Lafet et al, 2012;Reiser et al, 2012;Soubaras et al, 2012;Wallick and Giroldi, 2013;Kneller et al, 2013;and Michel and Sablon, 2016).…”

“…The data processing sequence consisted of swell and linear noise removal, suppression of seismic interference, debubbling using the far-field source signature modeled from the recorded near-field hydrophone, ghost wavefield elimination (Hu et al, 2014), water column static correction to compensate for water temperature variations, 3D surface-related multiple attenuation, and regularization onto a 25 × 25 m grid. A prestack Kirchhoff depth-migration algorithm was used to perform the imaging after a geologically consistent velocity model had been built through a multilayer horizon-constrained tomography (Masclet et al, 2015b). At the target level, the amplitude spectrum of the final data calculated in a 1300 ms vertical window show the −6 dB bandwidth ranging from 4 to 68 Hzsee Figure 2.…”