Method and apparatus for determining rough sea topography during a seismic survey

1. A method comprising:

acquiring seismic data by conducting a survey of a subsurface area of interest wherein the seismic data includes ghost data;

estimating a time-varying wave height above the subsurface area of interest during at least a portion of the survey, wherein the estimation of the wave height is based at least in part on a remote measurement of the wave height during the survey, wherein the wave height is measured using an underwater vehicle equipped with a synthetic aperture radar (SAR) system;

using the estimated time-varying wave height to characterize the ghost data; and

deghosting the seismic data based at least in part on the characterized ghost data.

2. The method of claim 1 , wherein a radar system is used to measure the wave height.

3. The method of claim 1 , wherein a lidar system is used to measure the wave height.

4. The method of claim 1 , wherein the wave height is measured using a sonar system.

5. The method of claim 1 , wherein the wave height is measured relative to a mean sea level.

6. The method of claim 1 , wherein the wave height is measured at a first frequency that is different that a second frequency at which the seismic data is recorded.

7. The method of claim 6 , wherein the first frequency is higher than the second frequency.

8. The method of claim 6 , wherein additional values for wave height are derived by interpolation.

9. The method of claim 1 , wherein the deghosting is performed using a wave equation deghosting algorithm.

10. A method comprising:

acquiring seismic data by conducting a survey of a subsurface area of interest wherein the seismic data includes ghost data;

remotely measuring a wave height above at least a portion of the subsurface area of interest during a portion of the survey, and wherein remotely measuring is coordinated with a firing of one or more seismic shots;

using the measured wave height to characterize the ghost data; and

deghosting the acquired seismic data based at least in part on the characterized ghost data.

11. The method of claim 10 , wherein the wave height is measured from an elevated position relative to a sea level.

12. The method of claim 10 , wherein the wave height is measured at a first frequency that is different that a second frequency at which the seismic data is recorded.

13. The method of claim 10 , wherein the deghosting is performed using a wave equation deghosting algorithm.

14. The method of claim 10 , wherein a radar system is used to measure the wave height.

15. The method of claim 10 , wherein a lidar system is used to measure the wave height.

16. A system, comprising:

a processor;

a non-transitory memory comprising program instructions executable by the processor to:

acquire seismic data by conducting a survey of a subsurface area of interest wherein the seismic data includes ghost data;

remotely estimate a wave height above the subsurface area of interest at pre-determined time intervals during the survey, wherein the estimation of the wave height is based at least in part on a remote measurement of the wave height, and wherein remotely estimating is coordinated with a firing of one or more seismic shots;

characterize the ghost data based at least in part on the estimated wave height; and

deghost the acquired survey data based at least in part on the characterized ghost data.

17. The system of claim 16 , further including a radar system for measuring the wave height.

18. The system of claim 16 , wherein the deghosting is performed using a wave equation deghosting algorithm.

19. A method comprising:

acquiring seismic data by conducting a survey of a subsurface area of interest wherein the seismic data includes ghost data;

remotely measuring wave height while acquiring the seismic data, wherein remotely measuring is coordinated with a firing of one or more seismic shots; and

deghosting the seismic data based at least in part on the measured wave height.