Method for improving seismic acquisitions utilising active ultralight seismic detection systems
The present invention concerns a method for determining the optimum positioning of source-receiver pairs capable of acquiring seismic data, comprising: a first step of identifying a zone of interest having been the subject of an earlier seismic acquisition, in order to obtain an image of the subsoil of same; a second step of obtaining seismic data acquired during the earlier seismic acquisition of said zone of interest during a time of interest; a third step of applying a partial or total demigration of seismic data, in order to determine the positions of each source-receiver pair having contributed to the image of said subsoil of said zone of interest during said time of interest; a fourth step of obtaining unprocessed traces for said source-receiver pair positions; a fifth step of selecting at least one optimum unprocessed trace from among said unprocessed traces; and a sixth step of determining the source-receiver pair positions corresponding to said at least one optimum unprocessed trace.
1. A method for determining the optimum positioning of source-receiver pairs capable of acquiring seismic data comprising the following steps:
a first step of identifying a zone of interest having been the subject of an earlier seismic acquisition previously used to obtain an image of the subsoil of same;
a second step of obtaining seismic data acquired during the earlier seismic acquisition of said zone of interest during a time of interest;
a third step of applying a demigration, in the form of an inverse plot of seismic rays, of said seismic data in order to determine the positions of each source-receiver pair having contributed to the image of said subsoil of said zone of interest during said time of interest;
a fourth step of obtaining unprocessed traces from said earlier seismic acquisition for said source-receiver pair positions;
a fifth step of selecting at least one optimum unprocessed trace from among said unprocessed traces;
a sixth step of determining optimum source-receiver pair positions corresponding to said optimum unprocessed trace; and
displaying a plot of the newly acquired seismic data as a function of time.
2. The method according to claim 1 , wherein the demigration of the third step is carried out by an octave range.
3. The method according to claim 2 , wherein the earlier seismic acquisition is a 4D acquisition.
4. The method according to claim 2 , wherein the fifth step further comprises the use of petro-elastic models in order to select the at least one optimum unprocessed traces.
5. The method according to claim 2 , wherein the fifth step further comprises a selection that takes account of the surface factors.
6. The method according to claim 2 , wherein the fifth step further comprises a selection that takes account of a reference zone used as calibration for seismic variations.
7. The method according to claim 1 , wherein the earlier seismic acquisition is a 4D acquisition.
8. The method according to claim 7 , wherein the fifth step further comprises a selection of unprocessed traces allowing to identify a change in the zone of interest.
9. The method according to claim 8 , wherein the fifth step further comprises the use of petro-elastic models in order to select the at least one optimum unprocessed traces.
10. The method according to claim 8 , wherein the fifth step further comprises a selection that takes account of the surface factors.
11. The method according to claim 7 , wherein the fifth step further comprises the use of petro-elastic models in order to select the at least one optimum unprocessed traces.
12. The method according to claim 7 , wherein the fifth step further comprises a selection that takes account of the surface factors.
13. The method according to claim 1 , wherein the fifth step further comprises the use of petro-elastic models in order to select the at least one optimum unprocessed traces.
14. The method according to claim 13 , wherein the fifth step further comprises a selection that takes account of the surface factors.
15. The method according to claim 1 , wherein the fifth step further comprises a selection that takes account of the surface factors.
16. The method according to claim 1 , wherein the fifth step further comprises a selection that takes account of a reference zone used as calibration for seismic variations.
17. The method according to claim 1 , wherein the third step further comprises the obtaining of a slope and emission and reception directions of the seismic waves for each source-receiver pair.
18. The method according to claim 1 , wherein the method further comprises a seventh step of placing source-receiver pairs at said optimum positions and an eighth step of acquiring new seismic data at said optimum positions.
19. The method according to claim 18 , wherein the eighth step is based on a slope and emission and reception directions of the seismic waves.
20. A method for acquiring seismic data comprising the following steps:
a first step of identifying a zone of interest having been the subject of an earlier seismic acquisition previously used to obtain an image of the subsoil of same;
a second step of obtaining seismic data acquired during the earlier seismic acquisition of said zone of interest during a time of interest;
a third step of applying a demigration, in the form of an inverse plot of seismic rays, of said seismic data in order to determine the positions of each source-receiver pair having contributed to the image of said subsoil of said zone of interest during said time of interest;
a fourth step of obtaining unprocessed traces from said earlier seismic acquisition for said source-receiver pair positions;
a fifth step of selecting at least one unprocessed trace from among said unprocessed traces;
a sixth step of determining source-receiver pair positions corresponding to said selected at least one unprocessed trace;
a seventh step of placing source-receiver pairs at said source-receiver pair positions corresponding to said selected at least one unprocessed trace; and
an eighth step of acquiring new seismic data at source-receiver pair positions corresponding to said selected at least one unprocessed trace; and
a ninth step of displaying a plot of the newly acquired seismic data as a function of time.