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Streamer and method for deploying the streamer for seismic data acquisition related to a subsurface of a body of water. The method includes a step of releasing into the body of water, from a vessel, a body having a predetermined length together with plural detectors provided along the body; a step o

Streamer and method for deploying the streamer for seismic data acquisition related to a subsurface of a body of water. The method includes a step of releasing into the body of water, from a vessel, a body having a predetermined length together with plural detectors provided along the body; a step of towing the body and the plural detectors such that the plural detectors are submerged; and a step of configuring plural birds provided along the body, to float at a predetermined depth from a surface of the water such that a first portion of the body has a curved profile while being towed underwater.

대표청구항 ▼

1. A streamer for collecting seismic data related to a subsurface of a body of water, the streamer comprising: a body having a predetermined length;plural detectors provided along the body; andplural birds provided along the body, wherein the birds are configured to float, when deployed under water,

1. A streamer for collecting seismic data related to a subsurface of a body of water, the streamer comprising: a body having a predetermined length;plural detectors provided along the body; andplural birds provided along the body, wherein the birds are configured to float, when deployed under water, at predetermined depths from a surface of the water such that a first portion of the body assumes a non-linear, variable-depth profile while being towed underwater, the non-linear, variable-depth profile being a parameterized curve, and a set of birds of the plural birds being disposed along the non-linear variable-depth profile,and the plural detectors being distributed along the parameterized curve at different depths from the surface of the water such that recorded seismic data has an increased low-frequency content relative to seismic data recorded with a same-depth streamer. 2. The streamer of claim 1, wherein the parameterized curve is one of a parabola, a circle or a hyperbola. 3. The streamer of claim 1, further comprising: a second portion having a flat profile connected to the first portion. 4. The streamer of claim 1, wherein the non-linear, variable-depth profile is described by z(h), which is a depth of a point of the first portion relative to the surface of the water, and satisfies the following equation: z⁡(h)=z0+s0⁢h⁡(1-0.5⁢(hhc))⁢⁢for⁢⁢h≤hc,where h is a horizontal distance between the point and a first detector provided on the body, z0 is a depth of the first detector relative to the surface of the water, s0 is a non-zero slope of the body at the first detector of the streamer, and hc is a predetermined horizontal distance between the first detector and an end of the non-linear, variable-depth profile. 5. The streamer of claim 4, further comprising: a second portion, connected to the first portion, the second portion being described by equation z(h)=z0+s0·0.5·hc for h>hc. 6. The streamer of claim 4, wherein a projection of the entire body on a line substantially parallel to the surface of the water is less than hc. 7. The streamer of claim 1, wherein the non-linear, variable-depth profile stays substantially the same during the towing. 8. The streamer of claim 1, further comprising: a second portion, connected to the first portion, the second portion having birds and detectors and having a flat profile. 9. The streamer of claim 8, wherein the second portion is substantially parallel to the surface of the water. 10. The streamer of claim 1, wherein the plural detectors include only hydrophones. 11. The streamer of claim 1, wherein no portion of the body, detectors or birds are anchored to the subsurface. 12. A method for seismic data acquisition related to a subsurface of a body of water, the method comprising: towing a body having a predetermined length together with plural detectors provided along the body;configuring plural birds provided along the body, to float at predetermined depths from a surface of the water such that a first portion of the body assumes a non-linear, variable-depth profile while being towed underwater, the non-linear, variable-depth profile being a parameterized curve, and a set of birds of the plural birds being disposed along the non-linear variable-depth profile; andrecording with the plural detectors the seismic data generated in the body of the water while towing the body, the plural detectors being distributed along the parameterized curve at different depths from the surface of the water such that recorded seismic data has an increased low-frequency content relative to seismic data recorded with a same-depth streamer. 13. The method of claim 12, wherein the parameterized curve is a parabola, a circle or a hyperbola. 14. The method of claim 12, wherein a second portion of the streamer has a flat profile and is connected to the first portion. 15. The method of claim 12, wherein the non-linear, variable-depth profile is described by z(h), which is a depth of a point of the first portion relative to the surface of the water, and satisfies the following equation: z⁡(h)=z0+s0⁢h⁡(1-0.5⁢(hhc))⁢⁢for⁢⁢h≤hc,where h is a horizontal distance between the point and a first detector provided on the body, z0 is a depth of the first detector relative to the surface of the water, s0 is a non-zero slope of the body at the first detector of the streamer, and hc is a predetermined horizontal distance between the first detector and an end of the non-linear, variable-depth profile. 16. The method of claim 15, further comprising: towing a second portion, connected to the first portion, the second portion being described by equation z(h)=z0+s0·0.5·hc for h>hc. 17. The method of claim 15, wherein a projection of the entire body on a line substantially parallel to the surface of the water is less than hc. 18. The method of claim 12, wherein the non-linear variable-depth profile stays substantially the same during the towing. 19. The method of claim 12, further comprising: towing a second portion, connected to the first portion, the second portion having birds and detectors and having a flat profile. 20. A method for deploying a streamer for seismic data acquisition related to a subsurface of a volume of water, the method comprising: releasing into the volume of water, from a vessel, a body having a predetermined length together with plural detectors provided along the body;towing the body and the plural detectors such that the plural detectors are submerged; andconfiguring plural birds provided along the body, to float at predetermined depths from a surface of the water such that a first portion of the body assumes a non-linear, variable-depth profile while being towed underwater, the non-linear, variable-depth profile being a parameterized curve, and a set of birds of the plural birds being disposed along the non-linear variable-depth profile,the plural detectors being distributed along the parameterized curve at different depths from the surface of the water to achieve ghost elimination. 21. A streamer for collecting seismic data related to a subsurface of a body of water, the streamer comprising: a body having a predetermined length;plural detectors provided along the body; andplural birds provided along the body,wherein the birds are configured to float, when deployed under water, at predetermined depths from a surface of the water such that a first portion of the body assumes a non-linear, variable-depth profile while being towed underwater, the non-linear, variable-depth profile being a parameterized curve, and a set of birds of the plural birds being disposed along the non-linear variable-depth profile, andthe plural detectors being distributed along the parameterized curve at different depths from the surface of the water to achieve ghost elimination. 22. The streamer of claim 21, wherein the parameterized curve includes one of a parabola, a circle or a hyperbola. 23. The streamer of claim 21, further comprising: a second portion having a flat profile connected to the first portion. 24. The streamer of claim 21, wherein the non-linear, variable-depth profile is described by z(h), which is a depth of a point of the first portion relative to the surface of the water, and satisfies the following equation: z⁡(h)=z0+s0⁢h⁡(1-0.5⁢(hhc))⁢⁢for⁢⁢h≤hc,where h is a horizontal distance between the point and a first detector provided on the body, z0 is a depth of the first detector relative to the surface of the water, s0 is a non-zero slope of the body at the first detector of the streamer, and hc is a predetermined horizontal distance between the first detector and an end of the non-linear, variable-depth profile. 25. The streamer of claim 24, further comprising: a second portion, connected to the first portion, the second portion being described by equation z(h)=z0+s0·0.5·hc for h>hc. 26. The streamer of claim 24, wherein a projection of the entire body on a line substantially parallel to the surface of the water is less than hc. 27. The streamer of claim 21, wherein the non-linear, variable-depth profile stays substantially the same during the towing. 28. The streamer of claim 21, further comprising: a second portion, connected to the first portion, the second portion having birds and detectors and having a flat profile. 29. The streamer of claim 28, wherein the second portion is substantially parallel to the surface of the water. 30. The streamer of claim 21, wherein the plural detectors include only hydrophones.