Three-Dimensional Deghosting
AssigneeWesternGeco L.L.C.
InventorJohan Olof Anders Robertsson
Life of this patent
Estimating the term…
Abstract
The method presented accounts for three-dimensional effects when deghosting marine seismic data. The method relies on having second-order spatial derivatives in the cross-line direction available. The second-order cross-line derivative can be estimated directly or through indirect measurements of other wavefield quantities and by using wave-equation techniques to compute the desired term. The method preferably employs either a multicomponent streamer towed in the vicinity of the sea surface, a twin-streamer configuration near the sea-surface, or a configuration of three streamers that are separated either vertically or horizontally to estimate the second-order vertical derivative of pressure.
Claims23
A method of de-ghosting seismic data, comprising the steps of:
- estimating the second-order cross-line derivative of pressure for marine seismic wavefield data through indirect measurements of other wavefield quantities;
- and
- using the estimated second-order cross-line derivative of pressure in a process to decompose the seismic wavefield data.
A method of de-ghosting seismic data, comprising the steps of:
- measuring the second-order cross-line derivative of pressure for marine seismic wavefield data using three streamers arranged side-by-side and spaced-apart within a fraction of the Nyquist wavenumber;
- and
- using the estimated second-order cross-line derivative of pressure and suitable techniques to decompose the seismic wavefield data.
Dependencies are inferred from the claim text.