Subsurface illumination, a hybrid wave equation-ray-tracing method
AssigneeGX Technology Corporation
InventorNikolaos Bernitsas
Life of this patent
Estimating the term…
Abstract
A method for improving illumination analysis in seismic data having steps of: selecting a model of the medium, a source and a receiver, a reflecting surface, finding a reflection point and the associated Fresnel zone according to Fermat principle using ray tracing, calculating the illumination in the Fresnel zone using the wave equation, repeating the illumination calculation for all frequencies all points on the reflecting surface and all source and the receiver pairs. The resulting illumination image may be used to assess the quality of or improve the seismic image of the same medium.
Claims11
A method for obtaining an improved seismic illumination image of a zone of interest, the method comprising steps of:
- a) having a model of the zone of interest, wherein the zone of interest is divided into plurality of cubes;
- b) having one or more seismic sources;
- c) having one or more seismic receivers;
- d) selecting a frequency of interest from a spectrum of frequencies;
- e) computing a wave function amplitude in a cube associated with a seismic source;
- f) computing a wave function amplitude in the cube associated with a seismic receiver;
- g) calculating the illumination in the cube associated with the source and the receiver by multiplying the source amplitude to the receiver amplitude;
- h) repeating the calculation of illumination in the cube for all frequencies in the spectrum;
- and
- i) summing the illumination in the cube associated with all frequencies in the spectrum;
- j) summing the illumination in the cube associated with all sources and receivers;
- k) repeating the illumination calculation for each cube in the seismic medium to obtain the illumination image of the zone of interest.
A method for obtaining an improved seismic illumination image of a zone of interest, the method comprising steps of:
- a) having a model of the zone of interest containing a seismic surface, wherein the medium is divided into cubes;
- b) having one or more sources;
- c) having one or more receivers;
- d) determining reflecting points on the seismic surface where a wave with a frequency from a source is reflected to a receiver;
- e) calculating illumination at the reflection points on the seismic surface for one selected frequency from the source and the receiver;
- repeating step d) and e) above for all frequencies;
- f) summing all of the illuminations for all frequencies and for all source and receiver pairs at all points on the surface.
A method for improving a seismic image with illumination compensation, the method comprising steps of:
- a) having a seismic image;
- b) having a seismic model for the seismic medium;
- c) obtaining an illumination image for the seismic medium;
- d) normalizing the seismic image with the illumination image.
Dependencies are inferred from the claim text.