Patent ID: 6272435
Filing Date: 2001-08-07
Classification: G01V

Abstract:
A method of generating a zero-offset trace, at a zero-offset location on a processing plane, for a time sampled recording, the time sampled recording having a source and receiver associated therewith, the time sampled recording having a source coordinate and a receiver coordinate associated therewith, the time sampled recording having an amplitude and a sampled time associated therewith, the method comprising:reading the source and receiver coordinates; wherein the source and receiver coordinates have a non-zero vertical offset associated therewith;computing a source-receiver offset from the source and receiver coordinates;determining an ellipsoid dependant upon the source-receiver offset, the sampled time, and the velocity of the medium, the ellipsoid having the source as one focus and the receiver as the other focus;determining a set of normal points on the ellipsoid, wherein a line from the zero-offset trace location to the ellipsoid is normal to the tangent of the ellipsoid at each of the normal points;determining the distance between each of the normal points and the zero-offset trace location;dividing twice the distance by the velocity of the medium, wherein the zero-offset travel time for each normal point is determined; andassigning an amplitude to each zero-offset travel time;wherein a zero-offset trace is generated.