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Apparatus, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method includes inputting data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors; applying a mi

Apparatus, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method includes inputting data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors; applying a migration procedure to the data to determine a first image of the subsurface; applying a mirror migration procedure to the data to determine a second image of the subsurface; joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; and generating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step.

대표청구항 ▼

1. A method for deghosting seismic data related to a subsurface of a body of water, the method comprising: recording, with detectors, seismic waves traveling from the subsurface, wherein the detectors are located on a streamer having birds that are controlled to achieve a curved portion of the strea

1. A method for deghosting seismic data related to a subsurface of a body of water, the method comprising: recording, with detectors, seismic waves traveling from the subsurface, wherein the detectors are located on a streamer having birds that are controlled to achieve a curved portion of the streamer;inputting data recorded by the detectors that are towed by a vessel, the data being associated with the waves travelling from the subsurface to the detectors;applying a migration procedure to the data to determine a first image of the subsurface;applying a mirror migration procedure to the data to determine a second image of the subsurface;joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; andgenerating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step. 2. The method of claim 1, wherein the deghosting is performed with a processing apparatus during an imaging phase and not in a preprocessing phase. 3. The method of claim 1, wherein no datuming step is performed on the data. 4. The method of claim 1, wherein a travelling angle of the waves propagating from the subsurface to the detectors or from a surface of the water to the detectors is not restricted. 5. The method of claim 1, wherein the data is three dimensional data and the migration, the mirror migration and the joint deconvolution are three dimensional procedures. 6. The method of claim 1, wherein the data are collected from streamers having a parameterized curved profile. 7. The method of claim 1, wherein the migration procedure comprises: recursively synthesizing an incident wave D(x, y, z+Δz, τ) at a depth z+Δz from a previous incident wave D(x, y, z, τ) at depth z. 8. The method of claim 1, wherein the mirror migration procedure comprises: recursively synthesizing an up-travelling wave U(x, y, z+Δz, τ) at a depth z+Δz from a previous up-travelling wave U(x, y, z, τ) at a depth z. 9. The method of claim 1, wherein the joint deconvoluting comprises: determining the reflectivity r(x, y, z), a minimum phase transfer function gmin(z), and a maximum phase transfer function gmax(z) based on equations: d1(x, y, z)=gmin(z)·r(x, y, z), andd2(x, y, z)=gmax(z)*r(x, y, z), wherein z is a depth of a point relative to the surface of the water, and x and y are coordinates of the point in a plane substantially parallel with the surface of the water. 10. The method of claim 9, wherein the gmin(z) and gmax(z) are three dimensional functions. 11. The method of claim 1, wherein the migration is a depth migration. 12. The method of claim 1, wherein the migration is a time migration. 13. The method of claim 1, wherein the joint deconvolution comprises: calculating a cost function C for determining the reflectivity, wherein the cost function C is given by: C=Σ(x,y,z)εV{[d1(x, y, z)−gmin(z)*r(x, y, z)]2+[d2(x, y, z)−gmax(z)*r(x, y, z)]2}, where d1(x, y, z) is the first image, d2(x, y, z) is the second image, gmin(z) is a minimum phase transfer function, gmax(z) is a maximum phase transfer function, z is a depth of a point relative to the surface of the water, x and y are coordinates of the point in a plane substantially parallel with the surface of the water, and V is a predetermined volume. 14. The method of claim 1, further comprising: applying a (τ, px, py) transform to the first image d1(x, y, z) and the second image d2(x, y, z), to transform the first image d1(x, y, z) into D1(px, py, τ) and the data d2(x, y, z) into D2(px, py, τ). 15. The method of claim 1, wherein the data includes recordings from hydrophones and geophones. 16. The method of claim 15, wherein a result of the migration procedure is d1(x, y, z) and a result of the mirror migration procedure is d2(x, y, z) for hydrophone type receivers and a result of the migration procedure is d3(x, y, z) and a result of the mirror migration procedure is d4(x, y, z) for geophones. 17. The method of claim 16, further comprising: generating the final image using a joint deconvolution of d1(x, y, z), d2(x, y, z), d3(x, y, z), and d4(x, y, z) and based on the following equations: d1(x, y, z)=ghmin(z)*r(x, y, z);d2(x, y, z)=ghmax(z)*r(x, y, z);d3(x, y, z)=ggmin(z)*c(z)*r(x, y, z); andd4(x, y, z)=ggmax(z)*c(z)*r(x, y, z), where ghmin and ggmin are minimum phase transfer functions, ghmax(z) and ggmax(z) are maximum phase transfer functions, z is a depth of a point relative to the surface of the water, x and y are coordinates of the point in a plane substantially parallel with the surface of the water, and c(z) is a calibration operator. 18. A processing device for deghosting seismic data related to a subsurface of a body of water, the processing device comprising: an interface configured to receive data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors, wherein the detectors are located on a streamer having birds that are controlled to achieve a curved portion of the streamer; anda processor connected to the interface and configured to, apply a migration procedure to the data to determine a first image of the subsurface,apply a mirror migration procedure to the data to determine a second image of the subsurface,joint deconvolute the first image and the second image for deghosting a reflectivity of the subsurface, andgenerate a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step. 19. The processing device of claim 18, wherein the processor is configured to deghost the final image during an imaging phase and not in a preprocessing phase. 20. The processing device of claim 18, wherein the processor is configured to perform no datuming step on the data. 21. The processing device of claim 18, wherein the processor is configured to handle the waves propagating from the subsurface to the detectors or from a surface of the water to the detectors with a travelling angle having no restriction. 22. The processing device of claim 18, wherein the data is three dimensional data and the migration, the mirror migration and the joint deconvolution are three dimensional procedures. 23. The processing device of claim 18, wherein the data are collected from streamers having a parameterized curved profile. 24. The processing device of claim 18, wherein the processor is configured to: determine the reflectivity r(x, y, z), a minimum phase transfer function gmin(z), and a maximum phase transfer function gmax(z) based on equations: d1(x, y, z)=gmin(z)·r(x, y, z), andd2(x, y, z)=gmax(z)*r(x, y, z), wherein z is a depth of a point relative to the surface of the water, and x and y are coordinates of the point in a plane substantially parallel with the surface of the water, and wherein the gmin(z) and gmax(z) are three dimensional functions. 25. The processing device of claim 18, wherein the processor is configured to execute the joint deconvolution by: calculating a cost function C for determining the reflectivity, wherein the cost function C is given by: C=Σ(x,y,z)εV{[d1(x, y, z)−gmin(z)*r(x, y, z)]2+[d2(x, y, z)−gmax(z)*r(x, y, z)]2}, where d1(x, y, z) is the first image, d2(x, y, z) is the second image, gmin(z) is a minimum phase transfer function, gmax(z) is a maximum phase transfer function, z is a depth of a point relative to the surface of the water, x and y are coordinates of the point in a plane substantially parallel with the surface of the water, and V is a predetermined volume. 26. The processing device of claim 18, wherein the processor is further configured to: apply a (τ, px, py) transform to the first image d1(x, y, z) and to the second image d2(x, y, z), to transform the first image d1(x, y, z) into D1(px, py, τ) and the data d2(x, y, z) into D2(px, py, τ). 27. The processing device of claim 18, wherein the data includes recordings from hydrophones and geophones. 28. The processing device of claim 27, wherein a result of the migration procedure is d1(x, y, z) and a result of the mirror migration procedure is d2(x, y, z) for hydrophone type receivers and a result of the migration procedure is d3(x, y, z) and a result of the mirror migration procedure is d4(x, y, z) for geophones. 29. The processing device of claim 28, wherein the processor is further configured to: generate the final image using a joint deconvolution of d1(x, y, z), d2(x, y, z), d3(x, y, z), and d4(x, y, z) and based on the following equations: d1(x, y, z)=ghmin(z)*r(x, y, z);d2(x, y, z)=ghmax(z)*r(x, y, z);d3(x, y, z)=ggmin(z)*c(z)*r(x, y, z); andd4(x, y, z)=ggmax(z)*c(z)*r(x, y, z), where ghmin and ggmin are minimum phase transfer functions, ghmax(z) and ggmax(z) are maximum phase transfer functions, z is a depth of a point relative to the surface of the water, x and y are coordinates of the point in a plane substantially parallel with the surface of the water, and c(z) is a calibration operator. 30. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a computer, implement a method for deghosting seismic data related to a subsurface of a body of water, the method comprising: recording, with detectors, waves traveling from the substance, wherein the detectors are located on a streamer having birds that are controlled to achieve a curved portion of the streamer;inputting data recorded by the detectors that are towed by a vessel, the data being associated with the waves travelling from the subsurface to the detectors;applying a migration procedure to the data to determine a first image of the subsurface;applying a mirror migration procedure to the data to determine a second image of the subsurface;joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; andgenerating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step.