Pressure Versus Vertical Velocity Full-Waveform Inversion of Wide-Angle, Ocean-Bottom Node Data from the North Sea
A. Robin, S.C. Singh, M. Noble and P.R. Williamson
Event name: 81st EAGE Conference and Exhibition 2019
Session: Poster: FWI Case Studies A
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 675.49Kb )
Price: € 20
For the characterisation of both hydrocarbon reservoirs and the surrounding geology, a depth model of the subsurface quantifying the elastic parameters is a desirable product. Full-waveform inversion (FWI) is an iterative approach that updates such initial model by minimising the misﬁt between real and modelled seismic data. Multicomponent ocean-bottom acquisitions are showing useful specificities in various domains of seismic imaging. In this paper, we compare on a real case (Alwyn North Field, UK, North Sea), pressure and vertical velocity components, when inverting for P-wave velocities with FWI, using large-angle, ocean-bottom data in a shallow-water environment. Vz component did not prove to be more useful than P component, as one could expect from its lower content in water-layer reverberations. P component might even be more useful since it led to a slightly more continuous model and since, unlike Vz component, its good S/N ratio allowed the estimation of a source. Better low frequencies from Vz component might allow us to make better use of Vz specificities.