Deep water high-resolution target detection

Abstract

A subsea target detection system is provided. The system may include a receiver array including a streamer. The system may include a plurality of receivers coupled to the streamer. The system may include a receiver array cross cable coupled to a first streamer and coupled to a second streamer. The receiver array cross cable may be disposed at a first depth in a body of water. The system may include a first deflector and a second deflector coupled to the receiver array cross cable. The system may include a source array including a first source and a second source. The source array may be coplanar with the receiver array. The system may include a source array cross cable coupled to the first source and coupled to the second source, the source array cross cable being disposed at a second depth in the body of water.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to U.S. Patent Application No. 16 / 446,408 filed on June 19, 2019 and U.S. Patent Application No. 16 / 446,411 filed on June 19, 2019, the entire contents of which are incorporated herein by reference. Background Art

[0003] Seismic or other operations performed on a piece of land may identify features or characteristics beneath the subsurface of the land being analyzed. Summary of the invention

[0004] At least one aspect of the present disclosure relates to a seabed target detection system. The seabed target detection system may include a receiver array. The receiver array may include a first streamer and a second streamer. The seabed target detection system may include a first plurality of receivers coupled to the first streamer. The seabed target detection system may include a second plurality of receivers coupled to the second streamer. The seabed target detection system may include a receiver array cross cable coupled to the first streamer and coupled to the second streamer. The receiver array cross cable may be disposed at a first depth of a body of water. The seabed target detection system may include a first deflector coupled to the receiver array cross cable. The seabed target detection system may include a second deflector coupled to the receiver array cross cable. The seabed target detection system may include a source array including a first source and a second source. The source array may be coplanar with the receiver array. The seabed target detection system may include a source array cross cable coupled to the first source and coupled to the second source. The source array cross cable may be disposed at a second depth of the body of water.

[0005] At least one aspect of the present disclosure relates to a method for detecting a subsea target. The method may include providing a receiver array. The receiver array may include a first streamer and a second streamer. The method may include coupling a first plurality of receivers to the first streamer and coupling a second plurality of receivers to the second streamer. The method may include coupling a receiver array cross cable to the first streamer and coupling the receiver array cross cable to the second streamer. The method may include disposing the receiver array cross cable at a first depth in a body of water. The method may include coupling a first deflector to the receiver array cross cable and coupling a second deflector to the receiver array cross cable. The method may include providing a source array. The source array may include a first source and a second source. The source array may be coplanar with the receiver array. The method may include coupling a source array cross cable to the first source and coupling the source array cross cable to the second source. The method may include disposing the source array cross cable at a second depth in the body of water.

[0006] At least one aspect of the present disclosure relates to a subsea target detection system. The subsea target detection system may include a receiver array. The receiver array may include a first streamer. The subsea target detection system may include a first plurality of receivers coupled to the first streamer. The subsea target detection system may include at least one of the first plurality of receivers to receive reflection data reflected from a target in the subsea during a first time period and to receive reflection data reflected from a target on the sea surface and in the subsea during a second time period. The first time period may be separated from the second time period by a first intermediate time period. The subsea target detection system may include a receiver array cross cable coupled to the first streamer. The receiver array cross cable may be disposed at a first depth in a body of water. The subsea target detection system may include a source array. The source array may include a first source. The subsea target detection system may include a source array cross cable coupled to the first source. The source array cross cable may be disposed at a second depth in a body of water.

[0007] At least one aspect of the present disclosure relates to a method for detecting a subsea target. The method may include providing a receiver array. The receiver array may include a first streamer. The method may include coupling a first plurality of receivers to the first streamer. The method may include receiving, by at least one of the first plurality of receivers, reflection data reflected from a target in the subsea during a first time period, and receiving reflection data reflected from a target in the sea surface and the subsea during a second time period. The first time period may be separated from the second time period by a first intermediate time period. The method may include coupling a receiver array cross cable to the first streamer. The method may include arranging the receiver array cross cable at a first depth in a body of water. The method may include providing a source array. The source array may include a first source. The method may include coupling a source array cross cable to the first source. The method may include arranging the source array cross cable at a second depth in the body of water. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, drawings, and claims.

[0009] Figure 1 A seabed target detection system according to an example embodiment is illustrated.

[0010] Figure 2 Diffraction surveying according to an example embodiment is illustrated.

[0011] Figure 3 A seabed target detection system according to an example embodiment is illustrated.

[0012] Figure 4 A seabed target detection system according to an example embodiment is illustrated.

[0013] Figure 5 A seabed target detection system according to an example embodiment is illustrated.

[0014] Figure 6 A seabed target detection system according to an example is illustrated.

[0015] Figure 7 A method for detecting a seabed target according to an example embodiment is illustrated.

[0016] Figure 8 A method for detecting a seabed target according to an example embodiment is illustrated.

[0017] Like reference numbers and designations throughout the several drawings indicate like elements. DETAILED DESCRIPTION

[0018] Surveying based on reflection as described herein can obtain information related to underground features.Acoustic signals can be reflected from underground lithological strata and be acquired, analyzed and interpreted.However, surveying based on reflection can cover narrow areas and collect a set of sparse data, both of which are factors that cause the increase in the required time for completing the survey.In addition, due to the resolution capability of surveying based on reflection, small shallow targets such as boulders buried in the seabed may be difficult to accurately image.These small targets can complicate or delay the arrangement of cable connections and communication lines between wind turbines, ocean or ocean bottom structures fixed to the seabed and these wind turbines, ocean or ocean bottom structures.

[0019] The present disclosure relates to systems and methods for seafloor target detection. Due to the limitations of reflection-based surveys, detecting small shallow targets in the seafloor can be challenging. Inefficiencies associated with increased survey times (such as greater risk of meteorological delays) can increase the operating costs of these surveys without providing an accurate map of seafloor obstacles. In addition, reflection-based surveys can be affected by noise problems that interfere with receiver positioning and data received by the receiver system, and the methods of the present disclosure can address these and other problems associated with performing surveys to detect seafloor targets.

[0020] The present disclosure relates to systems and methods for seafloor target detection. For example, a seafloor target detection system can provide an accurate map of seafloor obstacles. The system can include a receiver array including a streamer. The system can include a plurality of receivers coupled to the streamer. The system can include a receiver array cross cable coupled to a first streamer and coupled to a second streamer. The receiver array cross cable can be disposed at a first depth of a body of water. The system can include a first deflector and a second deflector coupled to the receiver array cross cable. The system can include a source array including a first source and a second source. The source array can be coplanar with the receiver array. The system can include a source array cross cable coupled to the first source and coupled to the second source, the source array cross cable being disposed at a second depth of the body of water.

[0021] Figure 1 An example of an undersea target detection system 100 for an ocean environment is shown, in which the systems and methods of the present disclosure can perform seismic surveys to detect undersea targets. The undersea target detection system 100 may include a receiver array 105. The receiver array 105 may include a first streamer 125. The receiver array 105 may include a second streamer 130. For example, the first streamer 125 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on a vessel 102. The first streamer 125 may be coupled to a receiver array cross cable 195. For example, the second streamer 130 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on a vessel 102. The second streamer 130 may be coupled to a receiver array cross cable 195.

[0022] The seafloor target detection system 100 may include a first plurality of receivers 110. The first plurality of receivers 110 may be coupled to a first streamer 125. The first plurality of receivers 110 may be disposed on the first streamer 125. The first plurality of receivers 110 may be coupled to the first streamer 125 along a line. The first plurality of receivers 110 may be evenly spaced along the first streamer 125. The first plurality of receivers 110 may receive diffraction data diffracted from a target in the seafloor. For example, the receivers in the first plurality of receivers 110 may be hydrophones or any other device capable of collecting seismic data. The seismic data may include reflection data indicating underground features of the seafloor. The seismic data may include diffraction data indicating underground features of the seafloor. The underground features of the seafloor may include small shallow targets such as boulders. The width of the small shallow target may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow target may be larger than 100 cm. These small shallow targets can be less than 10 centimeters. The first plurality of receivers 110 can be configured to detect sound waves reflected by seabed targets. The first plurality of receivers 110 can be configured to detect sound waves diffracted by seabed targets. The first plurality of receivers 110 can detect diffraction data diffracted from the edge of the target. For example, the first plurality of receivers 110 can detect diffraction data originating from the edge of a large target. The volume of a large target can be between 100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500 cubic meters). The volume of a large target can be less than 100 cubic meters. The volume of a large target can be greater than 100 cubic meters. A large target can be a shipping container. Diffraction data can originate from the corner of a shipping container. The first plurality of receivers 110 can detect targets with irregular surface features. For example, multiple receivers 110 can detect targets with small faces, edges, sharp boundaries or textures. Seabed targets can be completely buried in the seabed. Seabed targets can be partially buried in the seabed.

[0023] The seabed target detection system 100 may include a second plurality of receivers 120. The second plurality of receivers 120 may be coupled to the second streamer 130. The second plurality of receivers 120 may be disposed on the second streamer 130. The second plurality of receivers 120 may be coupled to the second streamer 130 along a line. The second plurality of receivers 120 may be evenly spaced along the second streamer 130. The second plurality of receivers 120 may receive diffraction data diffracted from a target in the seabed. For example, the receivers in the second plurality of receivers 120 may be hydrophones or any other device capable of collecting seismic data. The seismic data may include reflection data indicating underground features of the seabed. The seismic data may include diffraction data indicating underground features of the seabed. The underground features of the seabed may include small shallow targets such as boulders. The width of the small shallow target may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow target may be larger than 100 cm. These small shallow targets can be less than 10 centimeters. The second plurality of receivers 120 can be configured to detect sound waves reflected by the seabed target. The second plurality of receivers 120 can be configured to detect sound waves diffracted by the seabed target. The second plurality of receivers 120 can detect diffraction data diffracted from the edge of the target. For example, the second plurality of receivers 120 can detect diffraction data originating from the edge of a large target. The volume of a large target can be between 100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500 cubic meters). The volume of a large target can be less than 100 cubic meters. The volume of a large target can be greater than 100 cubic meters. A large target can be a shipping container. Diffraction data can originate from the corner of a shipping container. The second plurality of receivers 120 can detect targets with irregular surface features. For example, the second plurality of receivers 120 can detect targets with small faces, edges, sharp boundaries or textures. The seabed target can be completely buried in the seabed. Seabed targets may be partially buried in the seafloor.

[0024] The seabed target detection system 100 may include a receiver array cross cable 195. The receiver array cross cable 195 may be coupled to the first streamer 125. For example, the first streamer 125 may be bundled to the receiver array cross cable 195. The receiver array cross cable 195 may be coupled to the first streamer 125 at a first end of the first streamer 125. The first streamer 125 may be coupled to the receiver array cross cable 195 at a plurality of connection points. The receiver array cross cable 195 may be coupled to the second streamer 130. For example, the second streamer 130 may be bundled to the receiver array cross cable 195. The receiver array cross cable 195 may be coupled to the second streamer 130 at a first end of the second streamer 130. The second streamer 130 may be coupled to the receiver array cross cable 195 at a plurality of connection points. The receiver array cross cable 195 may be coupled to the source array cross cable 197. The receiver array cross cable 195 may be coupled to the first lateral cable 180. The receiver array crossover cable 195 may be coupled to the first lateral cable 180 at the first lateral cable distal end 171. The receiver array crossover cable 195 may be coupled to the first deflector 170. The receiver array crossover cable 195 may be coupled to the second deflector 175.

[0025] The receiver array crossover cable 195 may be coupled to the second transverse cable 185. The receiver array crossover cable 195 may be coupled to the second transverse cable 185 at the second transverse cable distal end 181. The receiver array crossover cable 195 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The receiver array crossover cable 195 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120.

[0026] The receiver array cross-cable 195 may be disposed at a first depth in the body of water.

[0027] The seabed target detection system 100 may include a first deflector 170. The first deflector 170 may be coupled to a receiver array cross cable 195. The first deflector 170 may be coupled to a first lateral cable 180. The first deflector 170 may be coupled to the first lateral cable 180 at the first lateral cable distal end 171. The first lateral cable 180 may be coupled to the receiver array cross cable 195. The first deflector 170 may be a deflector, downwind vane, or deflector that laterally redirects the movement of water through the deflector to generate a certain amount of lateral force. The deflector may be configured to redirect the flow of water through the deflector relative to the direction of movement of the deflector through the water. The deflector may include a steering device associated with the deflector. The steering device may redirect the flow of water to control the amount of lateral force generated by the deflector.

[0028] The seabed target detection system 100 may include a second deflector 175. The second deflector 175 may be coupled to a receiver array cross cable 195. The second deflector 175 may be coupled to a second lateral cable 185. The second deflector 175 may be coupled to the second lateral cable 185 at the first lateral cable distal end 171. The second lateral cable 185 may be coupled to the receiver array cross cable 195. The second deflector 175 may be a deflector, downwind vane or deflector that laterally redirects the movement of water through the deflector to generate a certain amount of lateral force. The deflector may be configured to redirect the flow of water through the deflector relative to the direction of movement of the deflector through the water. The deflector may include a steering device associated with the deflector. The steering device may redirect the flow of water to control the amount of lateral force generated by the deflector.

[0029] The undersea target detection system 100 may include a source array 127. The source array 127 may include a first source 150. For example, the first source 150 may generate source emissions. The first source 150 may generate acoustic waves. The source array 127 may generate acoustic signals received by the receiver array 105. For example, the source array 127 may include a first source 150 coupled to a source array cross cable 197. The source array 127 including the first source 150 may include a pattern of sources. The source array 127 may include a second source 155. For example, the second source 155 may generate source emissions. The second source 155 may generate acoustic waves. The source array 127 may generate acoustic signals received by the receiver array 105. For example, the source array 127 may include a second source 155 coupled to a source array cross cable 197. The source array 127 including the second source 155 may include a pattern of sources. The source array 127 may be coplanar with the receiver array 105. The plane of the source array 127 may be coplanar with the plane of the receiver array 105.

[0030] The seabed target detection system 100 may include a source array cross cable 197. The source array cross cable 197 may be coupled to the first source 150. The source array cross cable 197 may be connected to the first source 150. The source array cross cable 197 may be coupled to the first source 150 via a secondary cable. The source array cross cable 197 may be coupled to the second source 155. The source array cross cable 197 may be coupled to the second source 155. The source array cross cable 197 may be coupled to the second source 155 via a secondary cable. The source array cross cable 197 may be a power cable that transmits power from the vessel 102 to the first source 150. The source array cross cable 197 may be a power cable that transmits power from the vessel 102 to the second source 155. The source array cross cable 197 may be disposed at a second depth of the body of water.

[0031] The seabed target detection system 100 may include a first transverse cable 180 to couple with the first deflector 170. The first transverse cable 180 may be coupled with a source array cross cable 197. For example, the first transverse cable 180 may be a cable (e.g., a surface cable), a wire assembly, a tether, or a rope. The first transverse cable 180 may be connected with the source array cross cable 197. The first transverse cable 180 is coupled with a receiver array cross cable 195. The receiver array cross cable 195 may be coupled with the first deflector 170. The first transverse cable 180 may be directly coupled to the first deflector 170. The first transverse cable 180 may be coupled to the first deflector 170 via a secondary cable. The first transverse cable 180 may be coupled with the receiver array cross cable 195 to couple with the first deflector 170. The first transverse cable 180 may be coupled with the receiver array cross cable 195 to couple with the first deflector 170 at the first transverse cable distal end 171. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the first source 150. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the second source 155. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120.

[0032] The seabed target detection system 100 may include a second transverse cable 185 to couple with the second deflector 175. The second transverse cable 185 may be coupled with a source array cross cable 197. For example, the first transverse cable 185 may be a cable (e.g., a surface cable), a wire assembly, a tether, or a rope. The second transverse cable 185 may be connected with the source array cross cable 197. The second transverse cable 185 may be coupled with a receiver array cross cable 195. The receiver array cross cable 195 may be coupled with the second deflector 175. The second transverse cable 185 may be directly coupled to the second deflector 175. The second transverse cable 185 may be coupled to the second deflector 175 via a secondary cable. The second transverse cable 185 may be coupled with the receiver array cross cable 195 to couple with the second deflector 175. The second transverse cable 185 may be coupled with the receiver array cross cable 195 to couple with the second deflector 175. The second transverse cable 185 may be coupled with the receiver array cross cable 195 to couple with the second deflector 175 at the second transverse cable distal end 181. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the first source 150. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the second source 155. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120.

[0033] The seafloor target detection system 100 may include a vessel 102. The vessel 102 may tow a receiver array 105. The vessel 102 may tow a source array 127. The vessel 102 may tow the source array 127 in a towing direction 101. The vessel 102 may tow the receiver array 105 in the towing direction 101. The vessel may tow a source array cross-cable 197 before a receiver array cross-cable 195 relative to the towing direction 101. For example, the vessel 102 may tow the source array cross-cable 197 in the towing direction 101. The vessel 102 may tow the receiver array cross-cable 195 in the towing direction 101. A portion of the source array cross-cable 197 may be before a portion of the receiver array cross-cable 195 relative to the towing direction 101. The vessel 102 may be coupled to a first transverse cable 180. The vessel 102 may be coupled to a second transverse cable 185.

[0034] The seabed target detection system 100 may include a third streamer 135. The third streamer 135 may be located at a first distance from the first streamer 125. The third streamer 135 may be located at a first distance from the second streamer 130. The first distance may include a distance between 5 meters and 30 meters. For example, the first distance may be 12.5 meters. The first distance may be greater than 12.5 meters. The first distance may be less than 12.5 meters. The third streamer 135 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The receiver array 105 may include a third streamer 135. The receiver array 105 may include a plurality of third streamers 135. For example, the receiver array 105 may include one, two, three, or more third streamers 135.

[0035] The seabed target detection system 100 may include a fourth streamer 140. The fourth streamer 140 may be located at a first distance from the first streamer 125. The fourth streamer 140 may be located at a first distance from the second streamer 130. The first distance may include a distance between 5 meters and 30 meters. For example, the first distance may be 12.5 meters. The first distance may be greater than 12.5 meters. The first distance may be less than 12.5 meters. The fourth streamer 140 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The receiver array 105 may include a fourth streamer 140. The receiver array 105 may include a plurality of fourth streamers 140. For example, the receiver array 105 may include one, two, three, or more fourth streamers 140.

[0036] The seabed object detection system 100 may include a third source 160. The source array 127 may include the third source 160. The third source 160 may be located between the first streamer 125 and the third streamer 135. The third source 160 may be located between the first third streamer 135 and the second third streamer 135. The third source 160 may generate acoustic waves to be reflected by the seabed object and received by the first plurality of receivers 110. The third source 160 may generate acoustic waves to be diffracted by the seabed object and received by the first plurality of receivers 110. The source array 127 may include a plurality of third sources 160. For example, the source array 127 may include one, two, three, or more third sources 160. The third source 160 may generate acoustic waves to be reflected by the seabed object and received by the second plurality of receivers 120. The third source 160 may generate acoustic waves to be diffracted by the seabed object and received by the second plurality of receivers 120.

[0037] The seabed object detection system 100 may include a fourth source 165. The source array 127 may include the fourth source 165. The fourth source 165 may be located between the second streamer 130 and the fourth streamer 140. The fourth source 165 may be located between the first fourth streamer 140 and the second fourth streamer 140. The fourth source 165 may generate acoustic waves to be reflected by the seabed object and received by the first plurality of receivers 110. The fourth source 165 may generate acoustic waves to be diffracted by the seabed object and received by the first plurality of receivers 110. The source array 127 may include a plurality of fourth sources 165. For example, the source array 127 may include one, two, three, or more fourth sources 165. The fourth source 165 may generate acoustic waves to be reflected by the seabed object and received by the second plurality of receivers 120. The fourth source 165 may generate acoustic waves to be diffracted by the seabed object and received by the second plurality of receivers 120.

[0038] The seabed target detection system 100 may include a plurality of streamers 115. The plurality of streamers 115 may include a first streamer 125. The plurality of streamers 115 may include a second streamer 130. The plurality of streamers 115 may include one or more third streamers 135. For example, the plurality of streamers 115 may include three third streamers 135. The plurality of streamers 115 may include one or more fourth streamers 140. For example, the plurality of streamers 115 may include three fourth streamers 140. The plurality of streamers 115 may include exactly eight streamers. A plurality of receivers may be provided on the third streamer 135. A plurality of receivers may be provided on the fourth streamer 140.

[0039] The seabed target detection system 100 may include a plurality of sources. The plurality of sources may include a first source 150. The plurality of sources may include a second source 155. The plurality of sources may include one or more third sources 160. For example, the plurality of sources may include three third sources 160. The plurality of sources may include one or more fourth sources 165. For example, the plurality of sources may include three fourth sources 165. The plurality of sources may include exactly eight sources. The plurality of sources may generate acoustic signals. The first plurality of receivers 110 may receive reflection data reflected from a target in the seabed. The second plurality of receivers 120 may receive reflection data reflected from a target in the seabed 220. The first source 150 may generate an acoustic signal. The first plurality of receivers 110 may receive reflection data reflected from a target in the seabed 220 and generated by the first source 150. The second plurality of receivers 120 may receive reflection data reflected from a target in the seabed and generated by the first source 150. The second source 155 may generate an acoustic signal. The first plurality of receivers 110 may receive reflection data reflected from a target in the seabed and generated by the second source 155. The second plurality of receivers 120 may receive reflection data reflected from a target in the seafloor and generated by a second source 155 .

[0040] The seabed target detection system 100 may include a power cable 190 for providing power to the first source 150. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the first source 150. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the first source 150. The power cable 190 may be a plurality of power cables. The seabed target detection system 100 may include a power cable 190 for providing power to the second source 155. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the second source 155. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the second source 155.

[0041] The seabed target detection system 100 may include a power cable 190 for providing power to the third source 160. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the third source 160. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the third source 160. The power cable 190 may be a plurality of power cables. The seabed target detection system 100 may include a power cable 190 for providing power to the fourth source 165. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the fourth source 165. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the fourth source 165.

[0042] Figure 2Diffraction survey 200 is illustrated. Diffraction survey 200 may include receiver array 105 and source array 127. Source array 127 may generate source emission 215. Source emission 215 may pass through a medium (e.g., seawater) and diffract from seafloor target 210. Seafloor target 210 may be completely buried in seafloor 220. Seafloor target 210 may be partially buried in seafloor 220. Seafloor target 210 may include small shallow targets such as boulders. Small shallow targets may have a width between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). Small shallow targets may be larger than 100 cm. These small shallow targets may be smaller than 10 cm. Waves diffracted from seafloor target 210 may include diffraction data. Diffraction data may include diffraction waves 205. Receiver array 105 may receive diffraction data. For example, the receiver array 105 may receive the diffraction waves 205. The first plurality of receivers 110 of the receiver array 105 may receive diffraction data. For example, the first plurality of receivers 110 may receive the diffraction waves 205. Receivers in the first plurality of receivers 110 may receive the diffraction waves 205. The diffraction data may include the diffraction waves 205 originating from a seafloor target. The diffraction data may include the diffraction waves 205 generated from the source emission 215. The second plurality of receivers 120 in the receiver array 105 may receive the diffraction data. For example, the second plurality of receivers 120 may receive the diffraction waves 205. Receivers in the second plurality of receivers 120 may receive the diffraction waves 205. The diffraction data may include the diffraction waves 205 originating from a seafloor target. The diffraction data may include the diffraction waves 205 generated from the source emission 215. The first plurality of receivers 110 may detect diffraction data diffracted from an edge of a target. For example, the first plurality of receivers 110 may detect diffraction data originating from an edge of a large target. The second plurality of receivers 120 may detect diffraction data diffracted from an edge of a target. For example, the second plurality of receivers 120 may detect diffraction data originating from the edge of a large target. The volume of the large target may be between 100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500 cubic meters). The volume of the large target may be less than 100 cubic meters. The volume of the large target may be greater than 100 cubic meters. The large target may be a shipping container. The diffraction data may originate from the corner of the shipping container. The first plurality of receivers 110 may detect targets having irregular surface features. For example, the first plurality of receivers 110 may detect targets having small faces, edges, sharp boundaries, or textures. The second plurality of receivers 120 may detect targets having irregular surface features. For example, the second plurality of receivers 120 may detect targets having small faces, edges, sharp boundaries, or textures.

[0043] The first plurality of receivers 110 in the receiver array 105 may receive diffraction data. The diffraction data may include diffraction waves 205 diffracted from a seafloor target that is smaller than the Fresnel zone. The Fresnel zone is a reflection region from which most of the reflected energy returns, and the arrival time of the reflection differs from the arrival of the energy propagated from the energy source by less than half a cycle. Waves with such arrival times may constructively interfere and be detected by a single arrival. Therefore, it may be difficult to detect reflected waves from a target that is smaller than the Fresnel zone. However, the first plurality of receivers 110 in the receiver array 105 may detect diffraction waves from a target that is smaller than the Fresnel zone.

[0044] The second plurality of receivers 120 in the receiver array 105 may receive diffraction data. The diffraction data may include diffraction waves 205 diffracted from a seafloor target that is smaller than the Fresnel zone. The Fresnel zone is a reflection region from which most of the reflected energy returns, and the arrival time of the reflection differs from the arrival of the energy propagated from the energy source by less than half a cycle. Waves with such arrival times may enhance interference and be detected by a single arrival. Therefore, it may be difficult to detect reflected waves from a target that is smaller than the Fresnel zone. However, the second plurality of receivers 120 in the receiver array 105 may detect diffraction waves from a target that is smaller than the Fresnel zone.

[0045] Source array 127 may generate acoustic waves. The acoustic waves may include source emission 215. The acoustic waves may be diffracted from a target in the seafloor. Receiver array 105 may receive diffracted waves originating from a target in the seafloor. A central pair of sources may generate acoustic waves. A first source 150 may generate acoustic waves. A second source 155 may generate acoustic waves. Receivers in first plurality of receivers 110 of receiver array 105 may receive the diffracted waves. Receivers disposed on first streamer 125 may receive the diffracted waves. Receivers disposed on second streamer 130 may receive the diffracted waves. Receivers in second plurality of receivers 120 in receiver array 105 may receive the diffracted waves. Receivers disposed on first streamer 125 may receive the diffracted waves. Receivers disposed on second streamer 130 may receive the diffracted waves.

[0046] Figure 3 The subsea target detection system 100 is illustrated. The subsea target detection system 100 may include a first buoy 315 coupled to the first deflector 170. The first buoy 315 may be coupled to the first deflector 170. The first buoy 315 may be coupled to the first rod 320. The first buoy 315 may float on the sea surface 395. The sea surface 395 may include the sea surface 395. The first buoy 315 may be a floating device. The first buoy 315 may be anchored. The first buoy 315 may be allowed to drift with the ocean current. The first buoy 315 may be towed by the vessel 102.

[0047] The seabed target detection system 100 may include a second buoy 325 coupled to the second deflector 175. The seabed target detection system 100 may include a second buoy 325 coupled to the second deflector 175. The second buoy 325 may be connected to the second deflector 175. The second buoy 325 may be connected to the second rod 330. The second buoy 325 may be coupled to the first rod 320. The second buoy 325 may float on the sea surface 395. The second buoy 325 may be a floating device. The second buoy 325 may be anchored. The second buoy 325 may be allowed to drift with the ocean current. The second buoy 325 may be towed by the vessel 102.

[0048] The seabed object detection system 100 may include a first rod 320 coupled to the first buoy 315. The seabed object detection system 100 may include a first rod 320 coupled to the first deflector 170. The first rod 320 may separate the first buoy 315 from the first deflector 170. The first rod 320 may be coupled to the first deflector 170. The first rod 320 may be connected to the first deflector 170. The first rod 320 may be a structural component that separates the first buoy 315 from the first deflector 170.

[0049] The seabed target detection system 100 may include a second rod 330 coupled to the second buoy 325. The seabed target detection system 100 may include a second rod 330 coupled to the second deflector 175. The second rod 330 may separate the second buoy 325 from the second deflector 175. The second rod 330 may be coupled to the first deflector 170. The second rod 330 may be connected to the first deflector 170. The second rod 330 may be a structural component that separates the second buoy 325 from the second deflector 175.

[0050] The seabed target detection system 100 may include a first end streamer 335 of the plurality of streamers 115. The first end streamer 335 may be disposed at a first end 340 of a receiver array. The first end streamer 335 may include a first streamer 125. The first end streamer 335 may include a second streamer 130. The first end streamer 335 may include a third streamer 135. The first end streamer 335 may include a fourth streamer 140. The first end streamer 335 may include a first plurality of receivers 110 coupled to the first end streamer 335. The first end streamer 335 may include a second plurality of receivers 110 coupled to the first end streamer 335. The first end streamer 335 may be coupled to a receiver array cross cable 195. The first end streamer 335 may be disposed at a depth greater than a depth of a source array 127. The first end streamer 335 may be disposed at a depth less than a depth of a source array 127.

[0051] The seabed target detection system 100 may include a second end streamer 355 of the plurality of streamers 115. The second end streamer 355 may be disposed at a second end 360 of the receiver array. The second end 360 of the receiver array may be a distance from the first end 340 of the receiver array. The second end 360 of the receiver array may be less than 100 meters away from the first end 340 of the receiver array. For example, the second end 360 of the receiver array may be 87.5 meters away from the first end 340 of the receiver array. The second end streamer 355 may include a first streamer 125. The second end streamer 355 may include a second streamer 130. The second end streamer 355 may include a third streamer 135. The second end streamer 355 may include a fourth streamer 140. The second end streamer 355 may include a first plurality of receivers 110 coupled to the second end streamer 355. The second end streamer 355 may include a second plurality of receivers 110 coupled to the second end streamer 355. The second end streamer 355 may be coupled to the receiver array cross cable 195. The second end streamer 355 may be disposed at a depth greater than the depth of the source array 127. The second end streamer 355 may be disposed at a depth less than the depth of the source array 127.

[0052] The seabed target detection system 100 may include a first end source 345 of the plurality of sources. The first end source 345 may be disposed at a first end 350 of the source array. The first end source 345 may include the first source 150. The first end source 345 may include the second source 155. The first end source 345 may include the third source 160. The first end source 345 may include the fourth source 165. The first end source 345 may be coupled to the source array cross cable 197. The first end source 345 may be disposed at a depth less than the depth of the receiver array 105. The first end source 345 may be disposed at a depth greater than the depth of the receiver array 105.

[0053] The seabed target detection system 100 may include a second end source 365 of the plurality of sources. The second end source 365 may be disposed at a second end 370 of the source array. The second end 370 of the source array may be a distance from the first end 350 of the source array. The second end 370 of the source array may be a distance from the first end 350 of the source array. The second end 370 of the source array may be a distance from the first end 350 of the source array. The second end 370 of the source array may be less than 100 meters away from the first end 350 of the source array. For example, the second end 370 of the source array may be less than 87.5 meters away from the first end 350 of the source array. The second end source 365 may include the first source 150. The second end source 365 may include the second source 155. The second end source 365 may include the third source 160. The second end source 365 may include the fourth source 165. The second end source 365 may be coupled to the source array cross cable 197. The second end source 365 may be disposed at a depth less than the depth of the receiver array 105. The second end source 365 may be disposed at a depth greater than the depth of the receiver array 105.

[0054] The seabed target detection system 100 may include a receiver array cross-cable 195 disposed at a first depth 375. The seabed target detection system 100 may include a receiver array cross-cable 195 disposed at a first depth 375 greater than 6 meters below the sea surface 395. The seabed target detection system 100 may include a receiver array cross-cable 195 disposed at a first depth 375 less than 6 meters below the sea surface 395. The seabed target detection system 100 may include a receiver array cross-cable 195 disposed at a first depth 375 equal to 6 meters below the sea surface 395. The receiver array cross-cable 195 may be disposed at a depth greater than the depth of the source array cross-cable 197. The receiver array cross-cable 195 may be disposed at a depth less than the depth of the source array cross-cable 197. The receiver array cross-cable 195 may be disposed at a depth above the seabed.

[0055] The seabed target detection system 100 may include a source array cross-cable 197 disposed at a second depth 380. The seabed target detection system 100 may include a source array cross-cable 197 disposed at a second depth 380 greater than 4 meters below the sea surface 395. The seabed target detection system 100 may include a source array cross-cable 197 disposed at a second depth 380 less than 4 meters below the sea surface 395. The seabed target detection system 100 may include a source array cross-cable 197 disposed at a second depth 380 equal to 4 meters below the sea surface 395. The source array cross-cable 197 may be disposed at a depth greater than the depth of the receiver array cross-cable 195. The source array cross-cable 197 may be disposed at a depth less than the depth of the receiver array cross-cable 195. The source array cross-cable 197 may be disposed at a depth above the seabed.

[0056] The seafloor target detection system 100 may include a first depth controller 385 coupled to the first deflector 170. The first depth controller 385 may maintain the depth of the receiver array 105. The first depth controller 385 may be coupled to the first pole 320. The first depth controller 385 may be connected to the first pole 320. The first depth controller 385 may be coupled to the first buoy 315. The first depth controller 385 may be connected to the first buoy 315. The first depth controller 385 may be connected to the vessel 102 via a power cable 190. The power cable 190 may transmit power from the vessel 102 to the first depth controller 385.

[0057] The seafloor target detection system 100 may include a second depth controller 390 coupled to the second deflector 175. The second depth controller 390 may maintain the depth of the receiver array 105. The second depth controller 390 may maintain the depth of the receiver array 105. The second depth controller 390 may be coupled to the first pole 320. The second depth controller 390 may be connected to the first pole 320. The second depth controller 390 may be coupled to the first buoy 315. The second depth controller 390 may be connected to the first buoy 315. The second depth controller 390 may be coupled to the vessel 102 via a power cable 190. The power cable 190 may transmit power from the vessel 102 to the second depth controller 390.

[0058] The seabed object detection system 100 may include a source array 127 coplanar with the receiver array 105. For example, the source array 127 may define a first plane. The first plane may be a plane in which the first source 150 and the second source 155 are located. The first plane may be a plane in which the first source 150 and the third source 160 are located. The first plane may be a plane in which the first source 150 and the fourth source 165 are located. The receiver array 105 may define a second plane. The second plane may be a plane in which one of the first plurality of receivers 110 and one of the second plurality of receivers 120 are located. The second plane may be a plane in which a first receiver in the first plurality of receivers 110 and a second receiver in the first plurality of receivers 110 are located. The second plane may be a plane in which a first receiver in the second plurality of receivers 120 and a second receiver in the second plurality of receivers 120 are located.

[0059] Figure 4An example subsea target detection system 100 is shown. Subsea target detection system 100 may include vessel 102. Vessel 102 may tow receiver array 105. Vessel 102 may tow source array 127. Vessel 102 may tow source array 127 in tow direction 101. Vessel 102 may tow receiver array 105 in tow direction 101. Vessel may tow source array cross-cable 197 ahead of receiver array cross-cable 195 relative to tow direction 101. For example, vessel 102 may tow source array cross-cable 197 in tow direction 101. Vessel 102 may tow receiver array cross-cable 195 in tow direction 101. A portion of source array cross-cable 197 may be ahead of a portion of receiver array cross-cable 195 relative to tow direction 101. Vessel 102 may be coupled to first transverse cable 180. Vessel 102 may be coupled to second transverse cable 185.

[0060] The subsea target detection system 100 may include a first transverse cable 180. The first transverse cable 180 may include a tow line. The subsea target detection system 100 may include a first transverse cable 180 coupled to a first deflector 170. The first transverse cable 180 may be coupled to a source array cross cable 197. For example, the first transverse cable 180 may be a cable (e.g., a surface cable), a wire assembly, a tether, or a rope. The first transverse cable 180 may be connected to the source array cross cable 197. The first transverse cable 180 is coupled to a receiver array cross cable 195. The receiver array cross cable 195 may be coupled to the first deflector 170. The first transverse cable 180 may be directly coupled to the first deflector 170. The first transverse cable 180 may be coupled to the first deflector 170 via a secondary cable. The first transverse cable 180 may be coupled to the receiver array cross cable 195 to be coupled to the first deflector 170. The first transverse cable 180 may be coupled to the receiver array cross cable 195 to connect to the first deflector 170 at the first transverse cable distal end 171. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the first source 150. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the second source 155. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The first transverse cable 180 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120.

[0061] The subsea target detection system 100 may include a second transverse cable 185. The second transverse cable 185 may include a tow line. The subsea target detection system 100 may include a second transverse cable 185 coupled to the second deflector 175. The second transverse cable 185 may be coupled to a source array cross cable 197. For example, the first transverse cable 185 may be a cable (e.g., a surface cable), a wire assembly, a tether, or a rope. The second transverse cable 185 may be connected to the source array cross cable 197. The second transverse cable 185 may be coupled to a receiver array cross cable 195. The receiver array cross cable 195 may be coupled to the second deflector 175. The second transverse cable 185 may be directly coupled to the second deflector 175. The second transverse cable 185 may be coupled to the second deflector 175 via a secondary cable. The second transverse cable 185 may be coupled to the receiver array cross cable 195 to be coupled to the second deflector 175. The second transverse cable 185 may be coupled to the receiver array cross cable 195 to connect to the second deflector 175 at the second transverse cable distal end 181. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the first source 150. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the second source 155. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The second transverse cable 185 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120.

[0062] The seabed target detection system 100 may include a crossover cable. The crossover cable may include a source array crossover cable 197. The source array crossover cable 197 may be coupled to the first source 150. The source array crossover cable 197 may be connected to the first source 150. The source array crossover cable 197 may be coupled to the first source 150 via a secondary cable. The source array crossover cable 197 may be coupled to the second source 155. The source array crossover cable 197 may be coupled to the second source 155 via a secondary cable. The source array crossover cable 197 may be a power cable that transmits power from the vessel 102 to the first source 150. The source array crossover cable 197 may be a power cable that transmits power from the vessel 102 to the second source 155. The source array crossover cable 197 may be disposed at a second depth of the body of water.

[0063] The seabed target detection system 100 may include streamers. The streamers may include a first streamer 125. The streamers may include a second streamer 130. A receiver array cross-cable 195 may be coupled to the first streamer 125. For example, the first streamer 125 may be bundled to the receiver array cross-cable 195. The receiver array cross-cable 195 may be coupled to the first streamer 125 at a first end of the first streamer 125. The first streamer 125 may be coupled to the receiver array cross-cable 195 at a plurality of connection points. The receiver array cross-cable 195 may be coupled to the second streamer 130. For example, the second streamer 130 may be bundled to the receiver array cross-cable 195. The receiver array cross-cable 195 may be coupled to the second streamer 130 at a first end of the second streamer 130. The second streamer 130 may be coupled to the receiver array cross-cable 195 at a plurality of connection points. The receiver array cross-cable 195 may be coupled to the source array cross-cable 197. The receiver array cross-cable 195 may be coupled to the first lateral cable 180. The receiver array cross-cable 195 may be coupled to the first transverse cable 180 at the first transverse cable distal end 171. The receiver array cross-cable 195 may be coupled to the first deflector 170. The receiver array cross-cable 195 may be coupled to the second deflector 175. The receiver array cross-cable 195 may be coupled to the second transverse cable 185. The receiver array cross-cable 195 may be coupled to the second transverse cable 185 at the second transverse cable distal end 181. The receiver array cross-cable 195 may be a power cable that transmits power from the vessel 102 to the first plurality of receivers 110. The receiver array cross-cable 195 may be a power cable that transmits power from the vessel 102 to the second plurality of receivers 120. The receiver array cross-cable 195 may be disposed at a first depth in the body of water.

[0064] The streamer may include a third streamer 135. The seabed target detection system 100 may include a third streamer 135. The third streamer 135 may be located at a first distance from the first streamer 125. The third streamer 135 may be located at a first distance from the second streamer 130. The first distance may include a distance between 5 meters and 30 meters. For example, the first distance may be 12.5 meters. The third streamer 135 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The receiver array 105 may include a third streamer 135. The receiver array 105 may include a plurality of third streamers 135. For example, the receiver array 105 may include one, two, three, or more third streamers 135.

[0065] The streamer may include a fourth streamer 140. The seabed target detection system 100 may include a fourth streamer 140. The fourth streamer 140 may be located at a first distance from the first streamer 125. The fourth streamer 140 may be located at a first distance from the second streamer 130. The first distance may include a distance between 5 meters and 30 meters. For example, the first distance may be 12.5 meters. The fourth streamer 140 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The receiver array 105 may include a fourth streamer 140. The receiver array 105 may include a plurality of fourth streamers 140. For example, the receiver array 105 may include one, two, three, or more fourth streamers 140.

[0066] The seabed target detection system 100 may include a module. The module may include a receiver in the first plurality of receivers 110. The seabed target detection system 100 may include the first plurality of receivers 110. The first plurality of receivers 110 may be coupled to the first streamer 125. The first plurality of receivers 110 may be disposed on the first streamer 125. The first plurality of receivers 110 may be coupled to the first streamer 125 along a line. The first plurality of receivers 110 may be evenly spaced along the first streamer 125. The first plurality of receivers 110 may receive diffraction data diffracted from a target in the seabed. For example, the receivers in the first plurality of receivers 110 may be hydrophones or any other device capable of collecting seismic data. The seismic data may include reflection data indicating underground features of the seabed. The seismic data may include diffraction data indicating underground features of the seabed. The underground features of the seabed may include small shallow targets such as boulders. The width of the small shallow target can be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow target can be larger than 100 cm. These small shallow targets can be smaller than 10 cm. The first plurality of receivers 110 can be configured to detect sound waves reflected by the seabed target. The first plurality of receivers 110 can be configured to detect sound waves diffracted by the seabed target. The first plurality of receivers 110 can detect diffraction data diffracted from the edge of the target. For example, the first plurality of receivers 110 can detect diffraction data originating from the edge of a large target. The volume of the large target can be between 100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500 cubic meters). The volume of the large target can be less than 100 cubic meters. The volume of the large target can be greater than 100 cubic meters. The large target can be a shipping container. The diffraction data may originate from a corner of a shipping container. The first plurality of receivers 110 may detect an object having irregular surface features. For example, the first plurality of receivers 110 may detect an object having facets, edges, sharp boundaries, or textures. The seafloor object may be completely buried in the seafloor. The seafloor object may be partially buried in the seafloor.

[0067] The module may include a receiver in the second plurality of receivers 110. The seafloor target detection system 100 may include a second plurality of receivers 120. The second plurality of receivers 120 may be coupled to the second streamer 130. The second plurality of receivers 120 may be disposed on the second streamer 130. The second plurality of receivers 120 may be coupled to the second streamer 130 along a line. The second plurality of receivers 120 may be evenly spaced along the second streamer 130. The second plurality of receivers 120 may receive diffraction data diffracted from a target in the seafloor. For example, the receivers in the second plurality of receivers 120 may be hydrophones or any other device capable of collecting seismic data. The seismic data may include reflection data indicating subsurface features of the seafloor. The seismic data may include diffraction data indicating subsurface features of the seafloor. Subsurface features of the seafloor may include small shallow targets such as boulders. The width of the small shallow targets may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). Small shallow targets may be larger than 100 centimeters. These small shallow targets may be smaller than 10 centimeters. The second plurality of receivers 120 may be configured to detect sound waves reflected by seafloor targets. The second plurality of receivers 120 may be configured to detect sound waves diffracted by seafloor targets. The second plurality of receivers 120 may detect diffraction data diffracted from the edge of the target. For example, the second plurality of receivers 120 may detect diffraction data originating from the edge of a large target. The volume of a large target may be between 100 and 500 cubic meters (e.g., 100 cubic meters, 200 cubic meters, 300 cubic meters, 400 cubic meters, 500 cubic meters). The volume of a large target may be smaller than 100 cubic meters. The volume of a large target may be larger than 100 cubic meters. A large target may be a shipping container. Diffraction data may originate from the corner of a shipping container. The second plurality of receivers 120 may detect targets having irregular surface features. For example, the second plurality of receivers 120 may detect targets having small faces, edges, sharp boundaries, or textures. The seabed target may be completely buried in the seabed. The seabed target may be partially buried in the seabed.

[0068] The seabed target detection system 100 may include a first buoy 315. The seabed target detection system 100 may include a first buoy 315 coupled to the first deflector 170. The first buoy 315 may be coupled to the first deflector 170. The first buoy 315 may be coupled to the first rod 320. The first buoy 315 may float on the sea surface 395. The first buoy 315 may be a floating device. The first buoy 315 may be anchored. The first buoy 315 may be allowed to drift with the ocean current. The first buoy 315 may be towed by the vessel 102.

[0069] The seabed target detection system 100 may include a second buoy 325. The seabed target detection system 100 may include a second buoy 325 coupled to the second deflector 175. The seabed target detection system 100 may include a second buoy 325 coupled to the second deflector 175. The second buoy 325 may be connected to the second deflector 175. The second buoy 325 may be connected to the second rod 330. The second buoy 325 may be coupled to the first rod 320. The second buoy 325 may float on the sea surface 395. The second buoy 325 may be a floating device. The second buoy 325 may be anchored. The second buoy 325 may be allowed to drift with the ocean current. The second buoy 325 may be towed by the vessel 102.

[0070] The undersea object detection system 100 may include a relative global positioning system (RGPS) 405. The RGPS 405 may determine the location of an object on the earth relative to the location of another object. The RGPS 405 may determine the horizontal distance between one object to another object. The RGPS 405 may determine the vertical distance between one object to another object. The RGPS 405 may determine the offset between one object to another object. For example, the RGPS 405 may determine the location of the first deflector 170 relative to the vessel 102. The RGPS 405 may determine the location of the second deflector 175 relative to the vessel 102. The RGPS 405 may determine the relative positioning between two moving objects. The RGPS 405 may be connected to the first buoy 315. The RGPS 405 may be coupled to the first buoy 315. The RGPS 405 may be coupled to the second buoy 325. The RGPS 405 may be coupled to the second buoy 325.

[0071] The seabed target detection system 100 may include an acoustic transducer. The acoustic transducer 410 may convert an acoustic signal into an electrical signal. The electrical signal may be transmitted to the vessel 102. The acoustic transducer 410 may include a hydrophone. The acoustic transducer 410 may include a first plurality of receivers 110. The acoustic transducer 410 may include a first plurality of receivers 110 coupled to a first streamer 125. The acoustic transducer 410 may include a second plurality of receivers 120. The acoustic transducer 410 may include a second plurality of receivers 120 coupled to a second streamer 130. The acoustic transducer 410 may be disposed on a streamer. A plurality of acoustic transducers 410 may be disposed on a plurality of streamers 115.

[0072] The subsea target detection system 100 may include a T-connector 415. The T-connector 415 may include a tee connector. The T-connector 415 may include an electrical connection that connects three cables together. The T-connector 415 may connect the receiver array cross cable 195 to the receiver array 105. The T-connector 415 may couple the receiver array cross cable 195 to the receiver array 105. For example, the T-connector 415 may connect the receiver array cross cable 195 to the first streamer 125. The T-connector 415 may couple the receiver array cross cable 195 to the first streamer 125. For example, the T-connector 415 may connect the receiver array cross cable 195 to the second streamer 130. The T-connector 415 may couple the receiver array cross cable 195 to the second streamer 130. For example, the T-connector 415 may connect the receiver array cross cable 195 to the third streamer 135. The T-connector 415 may couple the receiver array cross cable 195 to the third streamer 135. For example, the T-connector 415 may connect the receiver array crossover cable 195 to the fourth streamer 140. The T-connector 415 may couple the receiver array crossover cable 195 to the fourth streamer 140.

[0073] The seafloor target detection system 100 may include a retrieval line 420. The retrieval line 420 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The retrieval line 420 may connect the vessel 102 to the receiver array cross-cable 195. The retrieval line 420 may connect the vessel 102 to the source array cross-cable 197.

[0074] The seabed target detection system 100 may include a signal cable 425. The signal cable 425 may include a power cable 190. The power cable 190 may provide power to the first source 150. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the first source 150. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the first source 150. The power cable 190 may be a plurality of power cables. The seabed target detection system 100 may include a power cable 190 for providing power to the second source 155. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the second source 155. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the second source 155.

[0075] The seabed target detection system 100 may include a power cable 190 for providing power to the third source 160. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the third source 160. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the third source 160. The power cable 190 may be a plurality of power cables. The seabed target detection system 100 may include a power cable 190 for providing power to the fourth source 165. For example, the power cable 190 may be a power cable that transmits power from the vessel 102 to the fourth source 165. The power cable 190 may be a power cable that transmits power from the source array cross cable 197 to the fourth source 165.

[0076] The subsea target detection system 100 may include a branch line 430. The branch line 430 may be a cable (e.g., a surface cable), a wire assembly, or any component capable of connecting a receiver to a recording device that may be located on the vessel 102. The branch line 430 may connect the first deflector 170 to the vessel 102. The branch line 430 may couple the first deflector 170 to the vessel 102. The branch line 430 may couple the first deflector 170 to the receiver array cross cable 195. The branch line 430 may connect the second deflector 175 to the vessel 102. The branch line 430 may couple the second deflector 175 to the vessel 102. The branch line 430 may couple the second deflector 175 to the receiver array cross cable 195.

[0077] Figure 5An example of a seabed target detection system 100 is shown. The seabed target detection system 100 may include at least one receiver of the first plurality of receivers 110. At least one receiver of the first plurality of receivers 110 may receive reflection data 505 reflected from a target in the seabed 220. The reflection data 505 may include a reflected wave. The reflection data 505 may include a microwave. At least one receiver of the first plurality of receivers 110 may receive a reflected wave from a target in the seabed 220. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from a seabed target 210. The seabed target 210 may be completely buried in the seabed 220. The seabed target 210 may be partially buried in the seabed 220. The seabed target 210 may include a small shallow target such as a boulder. The width of the small shallow target may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). Small shallow targets may be larger than 100 centimeters. These small shallow targets may be smaller than 10 centimeters. Waves reflected from seafloor targets 210 may include reflection data 505. Reflection data 505 may include reflected waves. Receiver array 105 may receive reflection data 505. For example, receiver array 105 may receive reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves. Reflection data 505 may include reflected waves originating from seafloor targets. Reflection data 505 may include reflected waves generated from source emission 215. Multiple sources of source array 127 may generate acoustic signals. First plurality of receivers 110 in receiver array 105 may receive reflection data 505 reflected from targets in seafloor 220. Reflection data 505 may include reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves reflected from targets in seafloor 220 and generated by sources in multiple sources in source array 127. Source array 127 may be disposed at distance 530 below sea surface 395. The receiver array 105 may be disposed at a distance 535 below the sea surface 395 .

[0078] At least one of the first plurality of receivers 110 may receive reflection data 515 reflected from the sea surface 395 and a target in the sea bottom 220. At least one of the first plurality of receivers 110 may receive reflection data 515 reflected from a target in the sea bottom 220 after reflecting from the sea surface 395. At least one of the first plurality of receivers 110 may receive a reflected wave from the sea surface 395. The reflection data 515 may include a reflected wave. The reflection data 515 may include a microwave. At least one of the first plurality of receivers 110 may receive a reflected wave from the sea surface 395. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from the sea surface 395. The wave reflected from the sea surface 395 may include reflection data 515. The reflection data 515 may include a reflected wave. The receiver array 105 may receive the reflection data 515. For example, the receiver array 105 may receive the reflected wave. The receivers of the first plurality of receivers 110 may receive the reflected wave. The reflection data 515 may include a reflected wave originating from the sea surface 395. Reflection data 515 may include reflected waves generated from source emission 215. The plurality of sources of source array 127 may generate acoustic signals. The first plurality of receivers 110 in receiver array 105 may receive reflection data 515 reflected from sea surface 395. Reflection data 515 may include reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves reflected from sea surface 395 and generated by sources in the plurality of sources in source array 127.

[0079] At least one receiver of the first plurality of receivers 110 may receive reflection data 520 reflected from the seabed 220 and reflected from the sea surface 395. At least one receiver of the first plurality of receivers 110 may receive reflection data 520 reflected from the sea surface 395 after reflecting from a target in the seabed 220. At least one receiver of the first plurality of receivers 110 may receive reflected waves from the seabed 220 and the sea surface 395. The reflection data 520 may include reflected waves. The reflection data 520 may include microwaves. At least one receiver of the first plurality of receivers 110 may receive reflected waves from the sea surface 395. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from the seabed 220. The waves reflected from the seabed 220 may include reflection data 520. The waves reflected from the seabed 220 and reflected from the sea surface 395 may include reflection data 520. The reflection data 520 may include reflected waves. The receiver array 105 may receive the reflection data 520. For example, the receiver array 105 may receive the reflected waves. Receivers in the first plurality of receivers 110 may receive reflected waves. Reflection data 520 may include reflected waves originating from the seafloor 220. Reflection data 520 may include reflected waves generated from source emission 215. The plurality of sources of source array 127 may generate acoustic signals. The first plurality of receivers 110 of receiver array 105 may receive reflection data 520 reflected from the seafloor 220 and reflected from the sea surface 395. Reflection data 520 may include reflected waves. Receivers in the first plurality of receivers 110 may receive reflected waves reflected from the seafloor 220 and generated by a source in the plurality of sources in source array 127.

[0080] At least one of the first plurality of receivers 110 may receive reflection data 525 reflected twice from the sea surface 395 and reflected from a target in the sea bottom 220. The reflection data 525 may include a reflected wave. The reflection data 525 may include a microwave. At least one of the first plurality of receivers 110 may receive a reflected wave from the sea surface 395. At least one of the first plurality of receivers 110 may receive reflection data 525 reflected from the sea surface 395 after being reflected from the sea surface 395 and then reflected by a target in the sea bottom 220. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from the sea surface 395. The reflected wave from the sea surface 395 may be reflected from the sea bottom 220. The reflected wave from the sea bottom 220 may be reflected again from the sea surface 395. The wave reflected from the sea surface 395 may include the reflection data 525. The wave reflected twice from the sea surface 395 may include the reflection data 525. The reflection data 525 may include a reflected wave. The receiver array 105 may receive the reflection data 525. For example, receiver array 105 may receive reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves. Reflection data 525 may include reflected waves originating from seafloor 220. Reflection data 525 may include reflected waves generated from source emission 215. Multiple sources in source array 127 may generate acoustic signals. First plurality of receivers 110 in receiver array 105 may receive reflection data 525 reflected twice from sea surface 395. Reflection data 525 may include reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves reflected twice from sea surface 395 and generated by sources in multiple sources in source array 127.

[0081] Figure 6An example of a seabed target detection system 100 is shown. The seabed target detection system 100 includes at least one receiver of the first plurality of receivers 110 to receive reflection data 505 reflected from a target in the seabed during a first time period 605. The reflection data 505 may include a reflected wave. At least one receiver of the first plurality of receivers 110 may receive a reflected wave from a target in the seabed 220 during the first time period 605. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from a seabed target 210. The seabed target 210 may be completely buried in the seabed 220. The seabed target 210 may be partially buried in the seabed 220. The seabed target 210 may include a small shallow target such as a boulder. The width of the small shallow target may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow target may be larger than 100 cm. These small shallow targets may be less than 10 centimeters. Waves reflected from seafloor targets 220 may include reflection data 505. Reflection data 505 may include reflected waves. Receiver array 105 may receive reflection data 505 during first time period 605. For example, receiver array 105 may receive reflected waves during first time period 605. Receivers in first plurality of receivers 110 may receive reflected waves. Reflection data 505 may include reflected waves originating from seafloor targets. Reflection data 505 may include reflected waves generated from source emission 215. Multiple sources in source array 127 may generate acoustic signals. First plurality of receivers 110 in receiver array 105 may receive reflection data 505 reflected from targets in seafloor 220 during first time period 605. Reflection data 505 may include reflected waves. Receivers in first plurality of receivers 110 may receive reflected waves reflected from targets in seafloor 220 and generated by sources in multiple sources in source array 127. The first time period 605 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by two times the wavelet velocity. The first time period 605 may be less than 1 millisecond. The first time period 605 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 15 milliseconds. The first intermediate time period 610 may be less than 10 milliseconds. The first intermediate time period 610 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 1 millisecond. The first intermediate time period 610 may be 0 milliseconds. The first intermediate time period may be at least 5 milliseconds.

[0082] At least one of the first plurality of receivers 110 may receive reflection data 515 reflected from targets in the sea surface 395 and the sea bottom 220 during the second time period 615. At least one of the first plurality of receivers 110 may receive reflected waves from targets in the sea surface 395 and the sea bottom 220 during the first time period 615. The reflection data 515 may include reflected waves. At least one of the first plurality of receivers 110 may receive reflected waves from targets in the sea surface 395 and the sea bottom 220 during the first time period 615. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from targets in the sea surface 395 and the sea bottom 220. Waves reflected from targets in the sea surface 395 and the sea bottom 220 may include reflection data 515. The reflection data 515 may include reflected waves. The receiver array 105 may receive reflection data 515 during the second time period 615. For example, the receiver array 105 may receive reflected waves during the second time period 615. The receivers of the first plurality of receivers 110 may receive reflected waves. The reflection data 515 may include reflected waves originating from a target in the seafloor 220. The reflection data 515 may include reflected waves generated from the source emission 215. The plurality of sources in the source array 127 may generate acoustic signals. The first plurality of receivers 110 in the receiver array 105 may receive the reflection data 515 reflected from the target in the sea surface 395 and the seafloor 220. The reflection data 515 may include reflected waves. The receivers in the first plurality of receivers 110 may receive reflected waves reflected from the target in the sea surface 395 and the seafloor 220 and generated by the sources in the plurality of sources in the source array 127. The second time period 615 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by two times the wavelet velocity. The second time period 615 may be less than 1 millisecond. The second time period 615 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 15 milliseconds. The first intermediate time period 610 may be less than 10 milliseconds. The first intermediate time period 610 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 1 millisecond. The first intermediate time period 610 may be 0 milliseconds. The first intermediate time period may be at least 5 milliseconds.

[0083] At least one of the first plurality of receivers 110 may receive reflection data 520 reflected from a target in the seabed 220 and reflected from the sea surface 395 during the third time period 620. At least one of the first plurality of receivers 110 may receive reflected waves from the target in the seabed 220 and the sea surface 395 during the third time period 620. The reflection data 520 may include the reflected waves. At least one of the first plurality of receivers 110 may receive reflected waves from the sea surface 395 during the third time period 620. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from the seabed 220. The waves reflected from the seabed 220 may include the reflection data 520. The waves reflected from the seabed 220 and reflected from the sea surface 395 may include the reflection data 520. The reflection data 520 may include the reflected waves. The receiver array 105 may receive the reflection data 520 during the third time period 620. For example, the receiver array 105 may receive the reflected waves. The receivers of the first plurality of receivers 110 may receive the reflected waves during the third time period 620. The reflection data 520 may include reflected waves originating from the seafloor 220. The reflection data 520 may include reflected waves generated from the source emission 215. The plurality of sources in the source array 127 may generate acoustic signals. The first plurality of receivers 110 in the receiver array 105 may receive the reflection data 520 reflected from the seafloor 220 and reflected from the sea surface 395 during the third time period 620. The reflection data 520 may include reflected waves. The receivers in the first plurality of receivers 110 may receive reflected waves reflected from the seafloor 220 and generated by the sources in the plurality of sources in the source array 127. The third time period 620 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by two times the wavelet velocity. The third time period 620 may be less than 1 millisecond. The third time period 620 may be less than 5 milliseconds. The second intermediate time period 625 may be less than 20 milliseconds. The second intermediate time period 625 may be less than 15 milliseconds. The second intermediate time period 625 may be less than 10 milliseconds. The second intermediate time period 625 may be less than 5 milliseconds. The second intermediate time period 625 may be less than 1 millisecond. The second intermediate time period 625 may be 0 milliseconds.

[0084] At least one of the first plurality of receivers 110 may receive reflection data 525 reflected twice from the sea surface 395 and reflected from a target in the sea bottom 220 during the fourth time period 630. The reflection data 525 may include a reflection wave. At least one of the first plurality of receivers 110 may receive a reflection wave from the sea surface 395 during the fourth time period 630. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from the sea surface 395. The reflected wave from the sea surface 395 may reflect from the sea bottom 220. The reflected wave from the sea bottom 220 may reflect again from the sea surface 395. The wave reflected from the sea surface 395 may include reflection data 525. The wave reflected twice from the sea surface 395 and reflected from the sea bottom 220 may include reflection data 525. The reflection data 525 may include a reflection wave. The receiver array 105 may receive the reflection data 525 during the fourth time period 630. For example, the receiver array 105 may receive the reflection wave. The receivers of the first plurality of receivers 110 may receive the reflection wave. The reflection data 525 may include a reflected wave originating from the sea surface 395. The reflection data 525 may include a reflected wave generated from the source emission 215. The plurality of sources in the source array 127 may generate an acoustic signal. The first plurality of receivers 110 in the receiver array 105 may receive the reflection data 525 reflected twice from the sea surface 395 and reflected from the sea bottom 220 during the fourth time period 630. The reflection data 525 may include a reflected wave. The receivers in the first plurality of receivers 110 may receive a reflected wave reflected twice from the sea surface 395 and reflected from the sea bottom 220 and generated by a source in the plurality of sources in the source array 127. The fourth time period 630 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by twice the wavelet velocity. The fourth time period 630 may be less than 1 millisecond. The fourth time period 630 may be less than 5 milliseconds.

[0085] The third intermediate time period 635 may be less than 30 milliseconds. The third intermediate time period 635 may be less than 25 milliseconds.

[0086] The third intermediate time period 635 may be less than 20 milliseconds. The third intermediate time period 635 may be less than 15 milliseconds.

[0087] The third intermediate time period 635 may be less than 10 milliseconds. The third intermediate time period 635 may be less than 5 milliseconds. The third intermediate time period 635 may be 0 milliseconds.

[0088] The seabed target detection system 100 includes at least one receiver in the second plurality of receivers 120 to receive reflection data 505 reflected from a target in the seabed during the first time period 605. The reflection data 505 may include a reflected wave. At least one receiver in the second plurality of receivers 120 may receive a reflected wave from a target in the seabed 220 during the first time period 605. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from a seabed target 210. The seabed target 210 may be completely buried in the seabed 220. The seabed target 210 may be partially buried in the seabed 220. The seabed target 210 may include a small shallow target such as a boulder. The width of the small shallow target may be between 10 cm and 100 cm (e.g., 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm). The small shallow target may be larger than 100 cm. These small shallow targets may be smaller than 10 cm. Waves reflected from seafloor target 220 may include reflection data 505. Reflection data 505 may include reflected waves. Receiver array 105 may receive reflection data 505 during first time period 605. For example, receiver array 105 may receive reflected waves during first time period 605. Receivers in second plurality of receivers 120 may receive reflected waves. Reflection data 505 may include reflected waves originating from seafloor target. Reflection data 505 may include reflected waves generated from source emission 215. Multiple sources in source array 127 may generate acoustic signals. Second plurality of receivers 120 in receiver array 105 may receive reflection data 505 reflected from target in seafloor 220 during first time period 605. Reflection data 505 may include reflected waves. Receivers in second plurality of receivers 120 may receive reflected waves reflected from target in seafloor 220 and generated by sources in multiple sources in source array 127. First time period 605 may be less than the difference between distance 530 below sea surface 395 and distance 535 below sea surface 395 divided by two times the wavelet velocity. The first time period 605 may be less than 1 millisecond. The first time period 605 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 15 milliseconds. The first intermediate time period 610 may be less than 10 milliseconds. The first intermediate time period 610 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 1 millisecond. The first intermediate time period 610 may be 0 milliseconds. The first intermediate time period may be at least 5 milliseconds.

[0089] At least one receiver in the second plurality of receivers 120 may receive reflection data 515 reflected from targets in the sea surface 395 and the sea bottom 220 during the second time period 615. At least one receiver in the second plurality of receivers 120 may receive reflected waves from targets in the sea surface 395 and the sea bottom 220 during the first time period 615. The reflection data 515 may include reflected waves. At least one receiver in the second plurality of receivers 120 may receive reflected waves from targets in the sea surface 395 and the sea bottom 220 during the first time period 615. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from targets in the sea surface 395 and the sea bottom 220. Waves reflected from targets in the sea surface 395 and the sea bottom 220 may include reflection data 515. The reflection data 515 may include reflected waves. The receiver array 105 may receive reflection data 515 during the second time period 615. For example, the receiver array 105 may receive reflected waves during the second time period 615. The receivers in the second plurality of receivers 120 may receive reflected waves. The reflection data 515 may include reflected waves originating from a target in the seafloor 220. The reflection data 515 may include reflected waves generated from the source emission 215. The plurality of sources in the source array 127 may generate acoustic signals. The second plurality of receivers 120 in the receiver array 105 may receive the reflection data 515 reflected from the target in the sea surface 395 and the seafloor 220. The reflection data 515 may include reflected waves. The receivers in the second plurality of receivers 120 may receive reflected waves reflected from the target in the sea surface 395 and the seafloor 220 and generated by the sources in the plurality of sources in the source array 127. The second time period 615 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by two times the wavelet velocity. The second time period 615 may be less than 1 millisecond. The second time period 615 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 15 milliseconds. The first intermediate time period 610 may be less than 10 milliseconds. The first intermediate time period 610 may be less than 5 milliseconds. The first intermediate time period 610 may be less than 1 millisecond. The first intermediate time period 610 may be 0 milliseconds. The first intermediate time period may be at least 5 milliseconds.

[0090] At least one receiver in the second plurality of receivers 120 may receive reflection data 520 reflected from a target in the seabed 220 and reflected from the sea surface 395 during the third time period 620. At least one receiver in the second plurality of receivers 120 may receive reflected waves from the target in the seabed 220 and the sea surface 395 during the third time period 620. The reflection data 520 may include the reflected waves. At least one receiver in the second plurality of receivers 120 may receive reflected waves from the sea surface 395 during the third time period 620. The source array 127 may generate source emissions 215. The source emissions 215 may pass through a medium (e.g., seawater) and reflect from the seabed 220. The waves reflected from the seabed 220 may include the reflection data 520. The waves reflected from the seabed 220 and reflected from the sea surface 395 may include the reflection data 520. The reflection data 520 may include the reflected waves. The receiver array 105 may receive the reflection data 520 during the third time period 620. For example, the receiver array 105 may receive the reflected waves. The receivers in the second plurality of receivers 120 may receive the reflected waves during the third time period 620. The reflection data 520 may include reflected waves originating from the seafloor 220. The reflection data 520 may include reflected waves generated from the source emission 215. The plurality of sources in the source array 127 may generate acoustic signals. The second plurality of receivers 120 in the receiver array 105 may receive the reflection data 520 reflected from the seafloor 220 and reflected from the sea surface 395 during the third time period 620. The reflection data 520 may include reflected waves. The receivers in the second plurality of receivers 120 may receive reflected waves reflected from the seafloor 220 and generated by the sources in the plurality of sources in the source array 127. The third time period 620 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by two times the wavelet velocity. The third time period 620 may be less than 1 millisecond. The third time period 620 may be less than 5 milliseconds. The second intermediate time period 625 may be less than 20 milliseconds. The second intermediate time period 625 may be less than 15 milliseconds. The second intermediate time period 625 may be less than 10 milliseconds. The second intermediate time period 625 may be less than 5 milliseconds. The second intermediate time period 625 may be less than 1 millisecond. The second intermediate time period 625 may be 0 milliseconds.

[0091] At least one receiver in the second plurality of receivers 120 may receive reflection data 525 reflected twice from the sea surface 395 and reflected from a target in the sea bottom 220 during the fourth time period 630. The reflection data 525 may include a reflection wave. At least one receiver in the second plurality of receivers 120 may receive a reflection wave from the sea surface 395 during the fourth time period 630. The source array 127 may generate a source emission 215. The source emission 215 may pass through a medium (e.g., seawater) and reflect from the sea surface 395. The reflected wave from the sea surface 395 may reflect from the sea bottom 220. The reflected wave from the sea bottom 220 may reflect again from the sea surface 395. The wave reflected from the sea surface 395 may include reflection data 525. The wave reflected twice from the sea surface 395 and reflected from the sea bottom 220 may include reflection data 525. The reflection data 525 may include a reflection wave. The receiver array 105 may receive the reflection data 525 during the fourth time period 630. For example, the receiver array 105 may receive the reflection wave. The receivers in the second plurality of receivers 120 may receive the reflection wave. The reflection data 525 may include a reflected wave originating from the sea surface 395. The reflection data 525 may include a reflected wave generated from the source emission 215. The plurality of sources in the source array 127 may generate an acoustic signal. The second plurality of receivers 120 in the receiver array 105 may receive the reflection data 525 reflected twice from the sea surface 395 and reflected from the sea bottom 220 during the fourth time period 630. The reflection data 525 may include a reflected wave. The receivers in the second plurality of receivers 120 may receive a reflected wave reflected twice from the sea surface 395 and reflected from the sea bottom 220 and generated by a source in the plurality of sources in the source array 127. The fourth time period 630 may be less than the difference between the distance 530 below the sea surface 395 and the distance 535 below the sea surface 395 divided by twice the wavelet velocity. The fourth time period 630 may be less than 1 millisecond. The fourth time period 630 may be less than 5 milliseconds.

[0092] The third intermediate time period 635 may be less than 30 milliseconds. The third intermediate time period 635 may be less than 25 milliseconds.

[0093] The third intermediate time period 635 may be less than 20 milliseconds. The third intermediate time period 635 may be less than 15 milliseconds.

[0094] The third intermediate time period 635 may be less than 10 milliseconds. The third intermediate time period 635 may be less than 5 milliseconds. The third intermediate time period 635 may be 0 milliseconds.

[0095] Figure 7A method for detecting a subsea target according to an embodiment is illustrated. In short, method 700 may include providing a receiver array (box 705). Method 700 may include coupling a receiver to a streamer (box 710). Method 700 may include coupling a receiver array cross cable to the streamer (box 715). Method 700 may include disposing the receiver array cross cable at a first depth (box 720). Method 700 may include coupling a deflector to the receiver array cross cable (box 725). Method 700 may include providing a source array (box 730). Method 700 may include coupling a source array cross cable to a source (box 735). Method 700 may include disposing the source array cross cable at a second depth (box 740). Method 700 may include coupling a buoy to the streamer (box 745).

[0096] The method 700 may include providing a receiver array (block 705). The method may include providing a receiver array 105. The receiver array 105 may include a first streamer 125. The receiver array 105 may include a second streamer 130. The method may include providing a plurality of streamers 115. The plurality of streamers 115 may include a first streamer 125. The plurality of streamers 115 may include a second streamer 130. The plurality of streamers 115 may include exactly eight streamers. The method may include providing a first end streamer 335 of the plurality of streamers 115. The method may include positioning the first end streamer 335 at a first end 340 of the receiver array. The method may include providing a second end streamer 355 of the plurality of streamers 115. The method may include positioning the second end streamer 355 at a second end 360 of the receiver array. The second end 360 of the receiver array may be at a distance of less than 100 meters from the first end 340 of the receiver array. The method may include towing the receiver array 105 in the towing direction 101 by the vessel 102. The method may include receiving, by the receiver array 105 , diffraction data including diffraction waves originating from a seafloor target and resulting from the source emission 215 .

[0097] The method 700 may include coupling receivers to streamers (block 710). The method may include coupling the first plurality of receivers 110 to the first streamer 125. The method may include coupling the first plurality of receivers 110 to the second streamer 130. The method may include coupling the first plurality of receivers 110 to the third streamer 135. The method may include coupling the first plurality of receivers 110 to the fourth streamer 140. The method may include coupling the second plurality of receivers 120 to the first streamer 125. The method may include coupling the second plurality of receivers 120 to the second streamer 130. The method may include coupling the second plurality of receivers 120 to the third streamer 135. The method may include coupling the second plurality of receivers 120 to the fourth streamer 140.

[0098] The method 700 may include coupling the receiver array crossover cable to the streamers (block 715). The method may include coupling the receiver array crossover cable 195 to the first streamer 125. The method may include coupling the receiver array crossover cable 195 to the second streamer 130. The method may include towing, by the vessel 102, the source array crossover cable 197 behind the receiver array crossover cable 195 relative to the towing direction 101.

[0099] The method 700 may include positioning the receiver array cross-cable at a first depth (block 720). The method may include positioning the receiver array cross-cable 195 at a first depth 375 in the body of water. The method may include positioning the receiver array cross-cable 195 at a first depth 375 greater than six meters below the sea surface 395.

[0100] The method 700 may include coupling a deflector to a receiver array cross cable (block 725). The method may include coupling a first deflector 170 to a receiver array cross cable 195. The method may include coupling a second deflector 175 to a receiver array cross cable 195. The method may include coupling a first depth controller 385 to the first deflector 170. The method may include coupling a second depth controller 390 to the second deflector 175. The second depth controller 390 and the first depth controller 385 may maintain the depth of the receiver array 105.

[0101] The method 700 may include providing a source array (block 730). The method may include providing a source array 127. The source array 127 may include a first source 150. The source array 127 may include a second source 155. The source array 127 may be coplanar with the receiver array 105. The method may include providing a plurality of sources. The method may include providing a plurality of sources in the source array 127. The plurality of sources may include the first source 150. The plurality of sources may include the second source 155. The plurality of sources may include a third source 160. The plurality of sources may include a fourth source 165. The plurality of sources may include exactly eight sources. The method may include providing a first end source 345 of the plurality of sources. The method may include arranging the first end source 345 at a first end 350 of the source array. The method may include providing a second end source 365 of the plurality of sources. The method may include arranging the second end source 365 at a second end 370 of the source array. The second end source 370 of the source array may be at a distance of less than 100 meters from the first end 350 of the source array. The method may include towing, by the vessel 102 , the source array 127 in the towing direction 101 .

[0102] The method 700 may include coupling a source array crossover cable to the source (block 735). The method may include coupling the source array crossover cable 197 to the first source 150. The method may include coupling the source array crossover cable 197 to the second source 155. The method may include towing the source array crossover cable 197 ahead of the receiver array crossover cable 195 by the vessel 102 relative to the towing direction 101.

[0103] The method 700 may include positioning the source array crossover cable at a second depth (block 740). The method may include positioning the source array crossover cable 197 at a second depth 380. The method may include positioning the source array crossover cable 197 at a second depth 380 greater than four meters below the sea surface 395.

[0104] The method 700 may include coupling the buoy to the deflector (block 745). The method may include coupling the first buoy 315 to the first deflector 170. The method may include coupling the second buoy 325 to the second deflector 175. The method may include coupling the first rod 320 to the first buoy 315. The method may include coupling the first rod 320 to the first deflector 170. The first rod 320 may separate the first buoy 315 from the first deflector 170. The method may include coupling the second rod 330 to the second buoy 325. The method may include coupling the second rod 330 to the second deflector 175. The second rod 330 may separate the second buoy 325 from the second deflector 175.

[0105] Figure 8 A method for detecting a subsea target according to an embodiment is illustrated. In short, method 800 may include providing a receiver array (box 805). Method 800 may include coupling a receiver to a streamer (box 810). Method 800 may include receiving reflection data (box 815). Method 800 may include coupling a receiver array cross cable to the streamer (box 820). Method 800 may include arranging the receiver array cross cable at a first depth (box 825). Method 800 may include providing a source array (box 830). Method 800 may include coupling a source array cross cable to a source (box 835). Method 800 may include arranging the source array cross cable at a second depth (box 840). Method 800 may include receiving diffraction data (box 845).

[0106] The method 800 may include providing a receiver array (block 805). The method may include providing a receiver array 105. The receiver array 105 may include a first streamer 125. The receiver array 105 may include a second streamer 130. The method may include providing a plurality of streamers 115. The plurality of streamers 115 may include a first streamer 125. The plurality of streamers 115 may include a second streamer 130. The plurality of streamers 115 may include exactly eight streamers. The method may include providing a first end streamer 335 of the plurality of streamers 115. The method may include arranging the first end streamer 335 at a first end 340 of the receiver array. The method may include providing a second end streamer 355 of the plurality of streamers 115. The method may include arranging the second end streamer 355 at a second end 360 of the receiver array. The second end 360 of the receiver array may be at a distance of less than 100 meters from the first end 340 of the receiver array. The method may include towing the receiver array 105 in the towing direction 101 by the vessel 102. The method may include receiving, by the receiver array 105 , diffraction data including diffraction waves originating from a seafloor target and resulting from the source emission 215 .

[0107] The method 800 may include coupling receivers to streamers (block 810). The method may include coupling the first plurality of receivers 110 to the first streamer 125. The method may include coupling the first plurality of receivers 110 to the second streamer 130. The method may include coupling the first plurality of receivers 110 to the third streamer 135. The method may include coupling the first plurality of receivers 110 to the fourth streamer 140. The method may include coupling the second plurality of receivers 120 to the first streamer 125. The method may include coupling the second plurality of receivers 120 to the second streamer 130. The method may include coupling the second plurality of receivers 120 to the third streamer 135. The method may include coupling the second plurality of receivers 120 to the fourth streamer 140.

[0108] The method 800 may include receiving reflection data (block 815). The method may include receiving reflection data by a first plurality of receivers. The method may include receiving reflection data reflected from a target in the seafloor by the first plurality of receivers. The method may include receiving reflection data by a second plurality of receivers. The method may include receiving reflection data reflected from a target in the seafloor by the second plurality of receivers. The method may include receiving reflection data reflected from a target in the seafloor by at least one receiver of the first plurality of receivers 110 during a first time period 605. The method may include receiving reflection data reflected from targets in the seafloor 220 by at least one receiver of the first plurality of receivers 110 during a second time period 615. The first time period 605 may be separated from the second time period 615 by a first intermediate time period 610. The method may include receiving, by at least one receiver of the first plurality of receivers 110, reflection data reflected from a target in the seafloor 220 and from the seafloor 395 during a third time period 620. The third time period may be separated from the first time period 605 by a second intermediate time period 625. The method may include receiving, by at least one receiver of the first plurality of receivers 110, reflection data reflected twice from the sea surface 395 and reflected from a target in the seafloor 220 during a fourth time period 630. The fourth time period 630 may be separated from the first time period 605 by a third intermediate time period 635.

[0109] The method may include receiving, by at least one of the second plurality of receivers 120, reflection data reflected from a target in the seafloor during a first time period 605. The method may include receiving, by at least one of the second plurality of receivers 120, reflection data reflected from a target in the seafloor 220 during a second time period 615. The first time period 605 may be separated from the second time period 615 by a first intermediate time period 610. The method may include receiving, by at least one of the second plurality of receivers 120, reflection data reflected from a target in the seafloor 220 during a third time period 620. The third time period 620 may be separated from the first time period 605 by a second intermediate time period 625. The method may include receiving, by at least one of the second plurality of receivers 120, reflection data reflected twice from the seafloor 395 and reflected from a target in the seafloor 220 during a fourth time period 630. The fourth time period 630 may be separated from the first time period 605 by a third intermediate time period 635.

[0110] The method 800 may include coupling the receiver array crossover cable to the streamers (block 820). The method may include coupling the receiver array crossover cable 195 to the first streamer 125. The method may include coupling the receiver array crossover cable 195 to the second streamer 130. The method may include towing, by the vessel 102, the source array crossover cable 197 behind the receiver array crossover cable 195 relative to the towing direction 101.

[0111] The method 800 may include positioning the receiver array cross-cable at a first depth (block 825). The method may include positioning the receiver array cross-cable 195 at a first depth 375 in the body of water. The method may include positioning the receiver array cross-cable 195 at a first depth 375 greater than six meters below the sea surface 395.

[0112] The method 800 may include providing a source array (block 830). The method may include providing a source array 127. The source array 127 may include a first source 150. The source array 127 may include a second source 155. The source array 127 may be coplanar with the receiver array 105. The method may include providing a plurality of sources. The method may include providing a plurality of sources in the source array 127. The plurality of sources may include the first source 150. The plurality of sources may include the second source 155. The plurality of sources may include a third source 160. The plurality of sources may include a fourth source 165. The plurality of sources may include exactly eight sources. The method may include providing a first end source 345 of the plurality of sources. The method may include arranging the first end source 345 at a first end 350 of the source array. The method may include providing a second end source 365 of the plurality of sources. The method may include arranging the second end source 365 at a second end 370 of the source array. The second end source 370 of the source array may be at a distance of less than 100 meters from the first end 350 of the source array. The method may include towing, by the vessel 102, the source array 127 in the towing direction 101. The method may include coupling the source array crossover cable 197 to the first source 150. The method may include coupling the source array crossover cable 197 to the second source 155. The method may include towing, by the vessel 102, the source array crossover cable 197 ahead of the receiver array crossover cable 195 relative to the towing direction 101.

[0113] The method 800 may include coupling a source array crossover cable to a source (block 835). The method may include coupling a source array crossover cable 197 to a first source 150. The method may include coupling a source array crossover cable 197 to a second source 155. The method may include towing, by the vessel 102, the source array crossover cable 197 ahead of the receiver array crossover cable 195 relative to the towing direction 101.

[0114] The method 800 may include positioning the source array crossover cable at a second depth (block 840). The method may include positioning the source array crossover cable 197 at a second depth 380. The method may include positioning the source array crossover cable 197 at a second depth 380 greater than four meters below the sea surface 395.

[0115] The method 800 may include receiving diffraction data (block 845). The method may include receiving the diffraction data by the first plurality of receivers 110. The method may include receiving the diffraction data diffracted from a target in the seafloor by the first plurality of receivers 110. The method may include receiving the diffraction data by the second plurality of receivers. The method may include receiving the diffraction data diffracted from a target in the seafloor by the second plurality of receivers 120.

[0116] The subject matter and operation embodiments described in this specification may be implemented in digital electronic circuits or in computer software, firmware or hardware, including the structures disclosed in this specification and their structural equivalents, or a combination of one or more of them. The subject matter described in this specification may be implemented as one or more computer programs (e.g., one or more circuits of computer program instructions) encoded on one or more computer storage media for execution by a data processing device or for controlling the operation of a data processing device. Alternatively or additionally, program instructions may be encoded on an artificially generated propagation signal, e.g., an electrical, optical or electromagnetic signal generated by a machine, which is generated to encode information for transmission to a suitable receiver device for execution by a data processing device. A computer storage medium may be or be included in a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. In addition, although a computer storage medium is not a propagation signal, a computer storage medium may be a source or destination of computer program instructions encoded in an artificially generated propagation signal. A computer storage medium may also be or be included in one or more separate components or media (e.g., multiple CDs, disks or other storage devices).

[0117] The operations described in this specification may be performed by a data processing device on data stored on one or more computer-readable storage devices or received from other sources. The term "data processing device" or "computing device" includes various devices, equipment and machines for processing data, including, for example, a programmable processor, a computer, a system on a chip, or a plurality of the foregoing or a combination thereof. The device may include a dedicated logic circuit, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). In addition to hardware, the device may also include code that creates an execution environment for the computer program in question, for example, code that constitutes processor firmware, a protocol stack, a database management system, an operating system, a cross-platform runtime environment, a virtual machine, or a combination of one or more thereof. The device and the execution environment may implement a variety of different computing model infrastructures, such as web services, distributed computing, and grid computing infrastructures.

[0118] A computer program (also referred to as a program, software, software application, script, or code) may be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and may be deployed in any form, including as a stand-alone program or as a circuit, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program may be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more circuits, subroutines, or portions of code). A computer program may be deployed to execute on one computer or on multiple computers located at one site or distributed over multiple sites and interconnected by a communications network.

[0119] Processors suitable for executing computer programs include, for example, microprocessors, and any one or more processors of digital computers. The processor can receive instructions and data from a read-only memory or a random access memory or both. The elements of a computer are a processor for performing actions according to instructions and one or more memory devices for storing instructions and data. The computer can include or be operably connected to receive data from one or more large-capacity storage devices for storing data, or to transfer data to one or more large-capacity storage devices for storing data, such as magnetic disks, magneto-optical disks, or optical disks, or both. The computer does not need to have such a device. In addition, the computer can be embedded in another device, such as a personal digital assistant (PDA), a global positioning system (GPS) receiver, or a portable storage device (such as a universal serial bus (USB) flash drive), to name just a few. Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, for example, semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0120] To provide interaction with a user, embodiments of the subject matter described in this specification may be implemented on a computer having a display device, such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user, and a keyboard and pointing device, such as a mouse or trackball, through which the user can provide input to the computer. Other types of devices may also be used to provide interaction with a user; for example, the feedback provided to the user may be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and any form of input from the user may be received, including acoustic, voice, or tactile input.

[0121] The embodiments described herein can be implemented in any of a variety of ways, including, for example, using hardware, software, or a combination thereof. When implemented in software, the software code can be executed on any suitable processor or processor collection, whether provided in a single computer or distributed among multiple computers.

[0122] Likewise, a computer may have one or more input and output devices. Among other things, these devices may be used to present a user interface. Examples of output devices that may be used to provide a user interface include a printer or display screen for visual presentation of the output and a speaker or other sound generating device for auditory presentation of the output. Examples of input devices that may be used for a user interface include a keyboard and a pointing device, such as a mouse, a touch pad, and a digitized tablet computer. As another example, a computer may receive input information through speech recognition or other auditory formats.

[0123] These computers can be interconnected in any suitable form through one or more networks, including local area networks or wide area networks (such as enterprise networks) and intelligent networks (IN) or the Internet. Such networks can be based on any suitable technology and can operate according to any suitable protocol, and can include wireless networks, wired networks or fiber optic networks.

[0124] A computer for implementing at least a portion of the functions described herein may include a memory, one or more processing units (also referred to herein as "processors"), one or more communication interfaces, one or more display units, and one or more user input devices. The memory may include any computer-readable medium, and may store computer instructions (also referred to herein as "processor executable instructions") for implementing the various functions described herein. The processing unit may be used to execute instructions. The communication interface may be connected to a wired or wireless network, a bus, or other communication device, and may therefore allow the computer to send communications to or receive communications from other devices. For example, a display unit may be provided to allow a user to view various information related to the execution of instructions. For example, a user input device may be provided to allow a user to make manual adjustments, make selections, enter data or various other information during the execution of instructions, or interact with the processor in any of a variety of ways during the execution of instructions.

[0125] The various methods or processes outlined herein may be encoded as software that can be executed on one or more processors using any of a variety of operating systems or platforms. In addition, such software may be written using any of a number of suitable programming languages ​​or programming or scripting tools, and may also be compiled into executable machine language code or intermediate code that is executed on a framework or virtual machine.

[0126] In this regard, various inventive concepts may be embodied as a computer-readable storage medium (or multiple computer-readable storage media) (e.g., computer memory, one or more floppy disks, optical disks, optical disks, tapes, flash memory, circuit configurations in field programmable gate arrays or other semiconductor devices or other non-transitory media or tangible computer storage media), which is encoded with one or more programs that, when executed on one or more computers or other processors, perform methods of implementing various embodiments of the solution discussed above. The computer-readable medium or multiple computer-readable media may be removable so that the one or more programs stored thereon can be loaded onto one or more different computers or other processors to implement various aspects of the present solution as discussed above.

[0127] In this document, the term "program" or "software" is used to refer to any type of computer code or computer executable instruction set that can be used to program a computer or other processor to implement various aspects of the above-described embodiments. The one or more computer programs that perform the methods of the present solution when executed need not reside on a single computer or processor, but can be distributed in a modular manner among multiple different computers or processors to implement various aspects of the present solution.

[0128] Computer executable instructions may be in various forms, such as program modules, which are executed by one or more computers or other devices. Program modules include routines, programs, objects, components, data structures, and other components that perform specific tasks or implement specific abstract data types. Generally, in various embodiments, the functionality of program modules may be combined or distributed as needed.

[0129] Likewise, data structures may be stored in computer-readable media in any suitable form. To simplify the description, data structures are shown as having fields that are associated by location in the data structure. Such relationships may also be achieved by assigning locations in a computer-readable medium that convey relationships between fields to the storage of the fields. However, any suitable mechanism may be used to establish relationships between information in the fields of a data structure, including by using pointers, tags, or other mechanisms that establish relationships between data elements.

[0130] Any reference to an embodiment or element or action of a system and method mentioned in the singular herein may include an embodiment comprising a plurality of these elements, and any reference to a plural form of any embodiment or element or action herein may include an embodiment comprising only a single element. References in the singular or plural form are not intended to limit the currently disclosed system or method, their parts, actions or elements to a single or multiple configurations. References to any action or element based on any information, action or element may include an embodiment of the action or element based at least in part on any information, action or element.

[0131] Any embodiment disclosed herein may be combined with any other embodiment, and references to "an embodiment," "some embodiments," "alternative embodiments," "various embodiments," "one embodiment," etc. are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment. These terms as used herein do not necessarily all refer to the same embodiment. Any embodiment may be combined, inclusively or exclusively, with any other embodiment in any manner consistent with the aspects and embodiments disclosed herein.

[0132] References to "or" may be interpreted as inclusive, such that any term described using "or" may indicate any of a single, more than one, and all of the described terms. References to at least one of a joint list of terms may be interpreted as inclusive OR to indicate any of a single, more than one, and all of the described terms. For example, references to "at least one of 'A' and 'B'" may include only "A," only "B," and both "A" and "B." Elements other than "A" and "B" may also be included.

[0133] The systems and methods described herein may be embodied in other specific forms without departing from their characteristics.The foregoing embodiments are illustrative rather than limiting of the described systems and methods.

[0134] Where a technical feature in the drawings, detailed description or any claim is followed by a reference numeral, the reference numeral is included to increase the intelligibility of the drawings, detailed description and claims. Therefore, neither the reference numerals nor their absence will have any limiting effect on the scope of any claim element.

[0135] The systems and methods described herein may be embodied in other specific forms without departing from their characteristics. The foregoing embodiments are illustrative rather than limiting of the described systems and methods. Therefore, the scope of the systems and methods described herein is indicated by the appended claims rather than the preceding description, and changes brought about by the meaning and scope of the equivalents of the claims are also included therein.

Claims

1. A seabed target detection system (100), comprising: A receiver array (105) comprising a first streamer (125) and a second streamer (130); a first plurality of receivers (110) coupled to the first streamer (125); a second plurality of receivers (120) coupled to the second streamer (130), wherein a first receiver of the first plurality of receivers (110) and a first receiver of the second plurality of receivers (120) define a plane; a receiver array crossover cable (195) coupled to the first streamer (125) and to the second streamer (130), the receiver array crossover cable (195) being disposed at a first depth (375) in the body of water; A first deflector (170) coupled to the receiver array crossover cable (195); a second deflector (175) coupled to the receiver array crossover cable (195); A source array (127) comprising a first source (150) and a second source (155); as well as a source array crossover cable (197) coupled to the first source (150) and coupled to the second source (155), the source array crossover cable (197) being disposed at a second depth (380) of the body of water, the first source (150) and the second source (155) being coplanar with the first receiver of the first plurality of receivers (110) and the first receiver of the second plurality of receivers (120), The receiver array (105) is configured to receive diffraction data, the diffraction data comprising diffracted waves (205) diffracted from a seafloor target that is smaller than a Fresnel zone, and the Fresnel zone is the region from which most of the reflected energy returns, and the arrival time of the reflections differs from the arrival of energy propagated from the source array (127) by less than half a cycle.

2. The seabed target detection system (100) according to claim 1, comprising: a first buoy (315) coupled to the first deflector (170); as well as A second buoy (325) is connected to the second deflector (175).

3. The seabed target detection system (100) according to claim 1, comprising: a first buoy (315) coupled to the first deflector (170); a second buoy (325) coupled to the second deflector (175); a first rod (320) coupled to the first buoy (315) and the first deflector (170), wherein the first rod (320) separates the first buoy (315) from the first deflector (170); as well as A second rod (330) is connected to the second buoy (325) and the second deflector (175), and the second rod (330) separates the second buoy (325) from the second deflector (175).

4. The seabed target detection system (100) according to claim 1, comprising: a plurality of streamers (115), the plurality of streamers (115) comprising the first streamer (125) and the second streamer (130), and the plurality of streamers (115) comprising exactly eight streamers; as well as A plurality of sources, the plurality of sources including the first source (150) and the second source (155), and the plurality of sources including exactly eight sources.

5. The seabed target detection system (100) according to claim 1, comprising: a plurality of streamer cables (115); a first end streamer (335) of the plurality of streamers (115), the first end streamer (335) being disposed at a first end (340) of a receiver array; and A second end streamer (355) among the plurality of streamers (115), the second end streamer (355) being disposed at a second end (360) of the receiver array, the second end (360) of the receiver array being at a distance of less than 100 meters from the first end (340) of the receiver array.

6. The seabed target detection system (100) according to claim 1, comprising: Multiple sources; a first end source (345) of the plurality of sources, the first end source (345) being disposed at a first end (350) of the source array; and A second end source (365) among the plurality of sources, the second end source (365) being arranged at a second end (370) of the source array, the second end (370) of the source array being at a distance of less than 100 meters from the first end (350) of the source array.

7. The seabed target detection system (100) according to claim 1, comprising: The receiver array cross-cable (195) is disposed at the first depth (375) greater than six meters below the sea surface (395); and The source array crossover cable (197) is disposed at the second depth (380) greater than four meters below the sea surface (395).

8. The seabed target detection system (100) according to claim 1, comprising: A first depth controller (385) connected to the first flow deflector (170); as well as A second depth controller (390) is connected to the second deflector (175), and the second depth controller (390) and the first depth controller (385) are used to maintain the depth of the receiver array (105).

9. The seabed target detection system (100) according to claim 1, comprising: A vessel (102) is used to tow the source array (127) and the receiver array (105) in a towing direction (101), the vessel (102) towing the source array crossover cable (197) ahead of the receiver array crossover cable (195) relative to the towing direction (101).

10. The seabed target detection system (100) according to claim 1, comprising: The receiver array receives diffraction data including diffraction waves (205) originating from a seafloor target (210) and generated from a source emission (215).

11. A method (700) for detecting a seabed target, comprising: Providing (705) a receiver array (105) including a first streamer (125) and a second streamer (130); coupling (710) a first plurality of receivers (110) to the first streamer (125) and coupling (710) a second plurality of receivers (120) to the second streamer (130), wherein a first receiver in the first plurality of receivers (110) and a first receiver in the second plurality of receivers (120) define a plane; coupling (715) a receiver array crossover cable (195) to the first streamer (125) and coupling (715) the receiver array crossover cable (195) to the second streamer (130); positioning (720) the receiver array cross-cable (195) at a first depth (375) in a body of water; coupling (725) a first deflector (170) to the receiver array crossover cable (195) and coupling (725) a second deflector (175) to the receiver array crossover cable (195); providing (730) a source array (127) including a first source (150) and a second source (155); coupling (735) a source array crossover cable (197) to the first source (150) and coupling (735) the source array crossover cable (197) to the second source (155); and positioning (740) the source array crossover cable (197) at a second depth (380) in the body of water, the first source (150) and the second source (155) being coplanar with the first receiver in the first plurality of receivers (110) and the first receiver in the second plurality of receivers (120), The receiver array (105) is configured to receive diffraction data, the diffraction data comprising diffracted waves (205) diffracted from a seafloor target that is smaller than a Fresnel zone, and the Fresnel zone is the region from which most of the reflected energy returns, and the arrival time of the reflections differs from the arrival of energy propagated from the source array (127) by less than half a cycle.

12. The method (700) according to claim 11, comprising: Connecting a first buoy (315) and the first deflector (170); as well as A second buoy (325) is coupled to the second deflector (175).

13. The method (700) of claim 11, comprising: Connecting a first buoy (315) and the first deflector (170); Connecting a second buoy (325) and the second deflector (175); coupling a first rod (320) to the first buoy (315) and the first deflector (170), the first rod (320) separating the first buoy (315) from the first deflector (170); as well as A second rod (330) is coupled to the second buoy (325) and the second deflector (175), the second rod (330) separating the second buoy (325) from the second deflector (175).

14. The method (700) of claim 11, comprising: providing a plurality of streamers (115), the plurality of streamers (115) comprising the first streamer (125) and the second streamer (130), and the plurality of streamers (115) comprising exactly eight streamers; and A plurality of sources is provided, the plurality of sources including the first source (150) and the second source (155), and the plurality of sources includes exactly eight sources.

15. The method (700) of claim 11, comprising: Providing a plurality of tow cables (115); Providing a first end streamer (335) of the plurality of streamers (115); Disposing the first end streamer (335) at a first end (340) of a receiver array; providing a second end streamer (355) of the plurality of streamers (115); and The second end streamer (355) is disposed at a second end (360) of the receiver array, the second end (360) of the receiver array being less than 100 meters away from the first end (340) of the receiver array.

16. The method (700) of claim 11, comprising: Provide multiple sources; providing a first end source (345) of the plurality of sources; Disposing the first end source (345) at a first end (350) of the source array; providing a second end source (365) of the plurality of sources; and The second end source (365) is arranged at a second end (370) of the source array, and the second end (370) of the source array is less than 100 meters away from the first end (350) of the source array.

17. The method (700) of claim 11, comprising: positioning the receiver array cross-cable (195) at the first depth (375) greater than six meters below the sea surface (395); as well as The source array crossover cable (197) is disposed at the second depth (380) greater than four meters below the sea surface (395).

18. The method according to claim 11, comprising: Connecting a first depth controller (385) to the first flow deflector (170); as well as A second depth controller (390) is coupled to the second deflector (175), and the second depth controller (390) and the first depth controller (385) are used to maintain the depth of the receiver array (105).

19. The method according to claim 11, comprising: towing the source array (127) and the receiver array (105) in a towing direction (101) by a vessel (102); as well as The source array crossover cable (197) is towed by the vessel (102) ahead of the receiver array crossover cable (195) relative to the towing direction (101).

20. The method according to claim 11, comprising: Diffraction data is received by the receiver array (105), the diffraction data comprising diffraction waves (205) originating from a seafloor target (210) and generated from a source emission (215).

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