Estimation of velocity-depth models for structural targets: A case history from the North Sea

Abstract

Three-dimensional seismic data from the North Sea were analyzed to remove the deleterious effect of the Zechstein diapiric formation on imaging the underlying Permian sands of Rotliegendes. This required accurate imaging of the overburden and delineating the geometry of the halite and anhydritedolomite units in the Zechstein formation. By using a field data case from the North Sea, we demonstrate an efficient strategy to conduct an inversion project for estimating velocity-depth models for 3-D structural targets. First, a set of utilities built around a workstation is needed to represent, visualize and edit 3-D velocity-depth models. Second, applications such as 3-D prestack traveltime inversion, and 3-D poststack and prestack depth migration are needed to estimate the velocity-depth model parameters. The latter two applications involve numerically-intensive computations and large inputoutput operations, and therefore, are best implemented on a powerstation, such as massively parallel processors. Finally, one needs to be able to efficiently download and archive large-scale data volumes using a serverstation.