f Depth conversion over known velocity anomalies - A comparison of methods

A comparison of depth conversion methods is presented using seismic data from the UK sector of the southern North Sea. Defining an accurate velocity field is a pre-requisite for successful depth conversion in this area, as lateral velocity variations within individual units are commonplace. These lateral velocity variations are caused by many factors but include regional uplift, localised salt tectonics, lithological variation and other anomalous effects. The purpose of this paper is firstly, to demonstrate how the choice of depth conversion method can affect the final result and secondly, to demonstrate how velocity anomalies, revealed during the building of the velocity field prior to depth conversion, can aid geological interpretation.