Patent Publication Number: US-2021188403-A1

Title: Methods and Systems for Underwater Application of Streamer Coating on Geophysical Streamers

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Application No. 62/950,024, filed Dec. 18, 2019, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     Techniques for marine geophysical surveying include seismic surveying and electromagnetic surveying, in which geophysical data may be collected from below the Earth&#39;s surface. Geophysical surveying has applications in mineral and energy exploration and production to help identify and monitor locations of hydrocarbon-bearing formations. Certain types of marine geophysical surveying, such as seismic or electromagnetic surveying, may include towing an energy source at a selected depth—typically above the seafloor—in a body of water. One or more streamers may also be towed in the water at selected depths—typically above the seafloor—by the same or a different vessel. The streamers are typically cables that include a plurality of sensors disposed thereon at spaced apart locations along the length of the cable. Some geophysical surveys locate sensors on ocean bottom cables or nodes in addition to, or instead of, streamers. The energy sources may be configured to generate a signal that is related to a parameter being measured by the sensor. At selected times, the energy source may be actuated to generate, for example, seismic or electromagnetic energy that travels downwardly into the subsurface rock. Energy that interacts with interfaces, generally at the boundaries between layers of rock formations, may be returned toward the surface and detected by the sensors on the streamers. The detected energy may be used to infer certain properties of the subsurface rock, such as structure, mineral composition, and fluid content, thereby providing information useful in the recovery of hydrocarbons. 
     Unfortunately, marine organisms may adhere to and then grow on nearly everything that is placed in water for extended periods of time, including marine geophysical sensor cables, such as towed streamers or ocean-bottom cables. For convenience, any such marine geophysical sensor cable will be referred to herein as a “streamer.” A streamer may include a marine streamer that comprises seismic sensors, electromagnetic sensors, or any combination thereof. 
     Marine growth (also known as biofouling) often refers to barnacle growth but is intended to also include the growth of mussels, oysters, algae, bacteria, tubeworms, slime, and other marine organisms. This marine growth is particularly problematic with streamers as the marine growth can increase drag resistance of the streamer, leading to increased fuel costs and/or reduced production speed. An additional problem with marine growth includes reduced data quality due to increased noise in the recorded data. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These drawings illustrate certain aspects of some of the embodiments of the present invention and should not be used to limit or define the invention. 
         FIG. 1  illustrates an embodiment of a marine seismic survey that employs an underwater application system. 
         FIG. 2A  illustrates an embodiment of a control system of the underwater application system that includes a mechanical valve. 
         FIG. 2B  illustrates an embodiment of the control system of the underwater application system that includes an electromechanical valve. 
         FIG. 3  illustrates an embodiment of a streamer coating on a streamer. 
         FIG. 4  illustrates a top view of an embodiment of the underwater application system coupled to a streamer cleaning unit (SCU). 
         FIG. 5  illustrates a side view of an embodiment of the underwater application system coupled to the SCU. 
         FIG. 6  illustrates an embodiment of multiple tanks to dispense a streamer coating onto a streamer that is submersed in a body of water. 
         FIG. 7  illustrates an embodiment of a dispensing device of the underwater application system. 
         FIG. 8  illustrates a flow chart depicting an operative sequence for the underwater application system, in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood that the present disclosure is not limited to particular devices or methods, which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. All numbers and ranges disclosed herein may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range are specifically disclosed. Although individual embodiments are discussed herein, the invention covers all combinations of all those embodiments. As used herein, the singular forms “a”, “an”, and “the” include singular and plural referents unless the content clearly dictates otherwise. Furthermore, the word “may” is used throughout this application in a permissive sense (i.e., having the potential to, being able to), not in a mandatory sense (i.e., must). The term “include,” and derivations thereof, mean “including, but not limited to.” The term “coupled” means directly or indirectly connected. If there is any conflict in the usages of a word or term in this specification and one or more patent or other documents that may be incorporated herein by reference, the definitions that are consistent with this specification should be adopted for the purposes of understanding this invention. 
     Embodiments relate generally to marine geophysical surveying. More particularly, embodiments relate to an underwater application system for application of a streamer coating to a surface of a streamer. The streamer coating can be applied to the streamer while the streamer is disposed underwater. The underwater application system may also be at least partially underwater during application of the streamer coating to the streamer. The streamer coating may protect the streamer by preventing marine growth, which would otherwise negatively interfere with streamer operation. Accordingly, by application of the streamer coating, operation of the streamer in marine surveying may be improved. 
     Referring now to  FIG. 1 , a marine geophysical survey system  2  that employs an underwater application system  4  is illustrated in accordance with embodiments of the disclosure. As will be discussed in more detail below, in some embodiments, the underwater application system  4  may be operable to apply a streamer coating to a streamer  6 . The streamer  6  may include a long cable (or other elongated structure) on which geophysical sensors  8  may be disposed at spaced apart locations along the length of the streamer  6 . In some embodiments, the marine geophysical survey system  2  may include a plurality of underwater application systems  4  configured to apply the streamer coating to a plurality of streamers  6 . The streamer coating may be any substance configured to limit marine growth on the streamer. The streamer coating may include an animal wax, a plant wax, a petroleum wax, a polyethylene wax, or some combination thereof. In some embodiments, the streamer coating includes lanolin. 
     In the illustrated embodiment, the marine geophysical survey system  2  may include a survey vessel  10  to which the plurality of streamers may be coupled. The survey vessel  10  may move along a surface  12  of a body of water  14 , such as a lake or ocean. The survey vessel  10  may include thereon equipment, shown generally at  16  and collectively referred to herein as a “recording system.” Recording system  16  may include computers or devices (e.g., storage devices, microprocessors, etc. (none shown separately)) for detecting and making a time indexed record of signals generated by each of geophysical sensors  8  (explained further below) and for actuating energy source  18  at selected times. The recording system  16  may also include devices (none shown separately) for determining the geodetic position of survey vessel  10  and various geophysical sensors  8 . 
     In some embodiments, the survey vessel  10  or another vessel may tow the at least one streamer  6  on which the geophysical sensors  8  may be disposed. As illustrated, the energy source  18  and the at least one streamer  6  may be towed above a water bottom  20 . The at least one streamer  6  may be a towed marine seismic streamer, a towed marine electromagnetic streamer, or a combination thereof. While not shown, some marine seismic surveys locate the geophysical sensors  8  on ocean bottom cables or nodes in addition to, or instead of, the streamer  6 . As illustrated, geophysical sensors  8  may be disposed at spaced apart locations on the streamer  6 . The geophysical sensors  8  may be, without limitation, seismic sensors such as geophones, hydrophones, or accelerometers, or electromagnetic field sensors, such as electrodes or magnetometers. The geophysical sensors  8  may generate response signals, such as electrical or optical signals, in response to detecting energy emitted from energy source  18  after the energy has interacted with formations  22  below water bottom  20 . In some embodiments, more than one streamer  6  may be towed by the survey vessel  10  or another vessel, and streamers  6  may be spaced apart laterally, vertically, or both laterally and vertically. The detected energy may be used to infer certain properties of the subsurface rock, such as structure, mineral composition, and fluid content, thereby providing information useful in the recovery of hydrocarbons and/or minerals. 
     In accordance with embodiments, a geophysical data product may be produced. The geophysical data product may include geophysical data and may be stored on a non-transitory, tangible, computer-readable medium. The geophysical data product may be produced offshore (e.g., by equipment on a vessel) or onshore (e.g., at a facility on land) either within the United States or in another country. If the geophysical data product is produced offshore or in another country, it may be imported onshore to a facility in the United States or another country. Once onshore, geophysical analysis, including further data processing, may be performed on the geophysical data product. 
     In some embodiments, the underwater application system  4  may be operable to apply the streamer coating to the streamer  6  while the streamer is being towed by the survey vessel. The underwater application system  4  may travel along the streamer  6  to apply the streamer coating. In some embodiments, the underwater application system  4  may be coupled to a streamer cleansing unit  24  (“SCU  24 ”) configured to travel along the streamer  6 . The SCU  24  may be configured to scrape or clean marine growth from the streamer  6  as the SCU  24  travels along the streamer  6 . In some embodiments, the underwater application system  4  may be configured to apply the streamer coating to the streamer  6  after the SCU  24  has scraped or cleaned the marine growth from the streamer  6 . The streamer coating may be applied to streamer  6  using any suitable technique, including, but not limited to, spray nozzles, brushes, etc. 
       FIG. 2A  illustrates an exemplary automated control system  26  of the underwater application system (e.g., the underwater application system  4  as shown on  FIG. 1 ), in accordance with some embodiments of the present disclosure. The control system  26  may include a regulator or valve  28  configured to regulate flow of the streamer coating through the underwater application system based on a depth and/or movement of a streamer (e.g., a streamer  6  as shown on  FIG. 1 ). The valve  28  may open and close based on ambient pressure (e.g., hydraulic pressure) in a body of water and may not require user intervention. The valve  28  is a non-limiting example of the control system  26  and other suitable regulators, valves, and/or control systems may be utilized, as should be understood by one having skill in the art, with the benefit of this disclosure. 
     In some embodiments, the control system  26  may be configured to cause the underwater application system to activate (e.g., dispense a coating or film) based at least in part on movement of the underwater application system. As illustrated, the valve  28  may include a body  30  that may include a first chamber  32  and a second chamber  34  that are separated by a diaphragm  36 . The diaphragm  36  may be made of a flexible material such as rubber or plastic, that may move based on ambient water pressure. An outer, movable, and rigid portion  38  of the body  30  may be attached to or in contact with a spring  40  that may be disposed within the first chamber  32 . The spring  40  may extend between and contact the portion  38  and the diaphragm  36 . The first chamber  32  and the second chamber  34  may be sealed (e.g., from sea water). In some embodiments, seals  42  such as O-ring(s) may be disposed around the portion  38 . 
     A third chamber  44  may be disposed within the second chamber  34 . The second chamber  34  may be in fluid communication with the third chamber  44  via a passage  46  disposed between the second chamber  34  and the third chamber  44 . A plug or sealing member  48  may extend from the third chamber  44  to the second chamber  34 . As illustrated, the sealing member  48  may extend through the passage  46  from a wall  50  of the third chamber  44 . A distal end  52  of the sealing member  48  may contact the diaphragm  36 . The sealing member  48  may extend through a spring  54  that extends from the wall  50  to the passage  46 . The spring  54  may include an end cap  56  that abuts a flange  58  of the sealing member  48 . The spring  54  may be compressed between the flange  58  and the wall  50  of the third chamber  44 . The flange  58  may seal against the passage  46 . In some embodiments, ambient water pressure (e.g., a threshold pressure) indicated by directional arrow  60  may cause the portion  38  to move inward to compress and cause the spring  40  to push against the diaphragm  36 . The ambient water pressure may depend on depth and/or movement of the underwater application system  4  and/or the streamer  6 . As the diaphragm  36  is pushed inward or flexes, the flange  58  of the sealing member  48  is moved away from the passage  46  thereby compressing the spring  54  in the third chamber  44  against the wall  50  and allowing a pressurized fluid that enters the third chamber  44  via an inlet  62  to enter the second chamber  34  through the passage  46 . The inlet  62  may be coupled to a high-pressure source, tank, or vessel, for example. The pressurized fluid may exit the second chamber  34  via an outlet  64  which may be coupled to a dispensing device, in some embodiments. When the ambient water pressure is below a threshold pressure, the springs  40  and  54  may expand to their initial uncompressed or expanded configuration to close the passage  46  and prevent any fluid in the third chamber  44  from passing to the second chamber  34 . It should be noted that stiffness of the springs may be chosen depending on a desired depth (e.g., a predetermined depth) of operation or velocity of the survey vessel  10  or environmental conditions at sea. For example, a stiffer spring may be utilized for depths with greater pressures, whereas less stiff springs may be utilized for shallower depths with lesser pressures. The valve  28  may allow the underwater application system  4  (e.g., shown on  FIG. 1 ) to dispense the streamer coating in response to the underwater application system moving along the streamer and/or reaching a threshold ambient water pressure or depth. 
     As previously noted, the valve  28  is a non-limiting example of the control system  26  and other suitable regulators, valves, or control systems may be utilized, as should be understood by one having skill in the art, with the benefit of this disclosure. In some embodiments, the valve  28  may be replaced with an electromechanical valve such as a solenoid valve. 
       FIG. 2B  illustrates the control system  26  including an electromechanical valve  66 , in accordance with some embodiments of the present disclosure. The electromechanical valve  66  may be in communication (e.g., wires or wireless) with a motion detector  68 , depth gauge  70 , pressure sensor  72 , and/or speed sensor  74 . The electromechanical valve  66  may pass fluid via an inlet  63  and an outlet  65 . In some embodiments, the inlet  63  may be coupled to a high-pressure source, tank, or vessel. The outlet  65  may be coupled to a dispensing device, for example. The electromechanical valve  66  may be configured to open or close based on detected motion, depth, pressure, and/or speed measurements. In certain embodiments, a computer  76  that is in communication with the electromechanical valve  66  and associated sensor components (e.g., the motion detector  68 , the depth gauge  70 , the pressure sensor  72 , and/or the speed sensor  74 ), may be programmed to open or close the electromechanical valve  66  based on threshold values for motion detection, depth, pressure, and/or speed, thereby dispensing the streamer coating. The computer  76  may be disposed on the SCU  24  or on the underwater application system  4 , as shown on  FIG. 1 , for example. The computer  76  may include one or more processing devices, and the memory may include one or more tangible, non-transitory, machine-readable media. By way of example, such machine-readable media can include RAM, ROM, EPROM, EEPROM, or optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by the processor or by other processor-based devices (e.g., mobile devices). In some embodiments, the memory is configured to store controller instructions executable by the processor to output various control system signals. For example, the processor may execute the controller instructions to activate the underwater application system  4  by opening or closing the electromechanical valve  66 . 
       FIG. 3  illustrates the streamer  6  with the streamer coating  78 , in accordance with some embodiments of the present disclosure. As previously described, the streamer coating  78  may be applied to streamer  6  while the streamer is towed by the survey vessel. The streamer coating  78  may also be applied to streamer components (not shown), such as position control devices that include one or more wings, for example. The streamer coating  78  may have any suitable thickness based on a number of factors, including, but not limited to, water temperature, type of streamer coating, and travel speed of the underwater application system along the streamer. In some embodiments, the streamer coating  78  may have a thickness of about 0.01 millimeter to about 1 millimeter. It should be understood that the present embodiments should not be limited to the disclosed range for thickness of the streamer coating  78 , but rather, in some embodiments, the streamer coating  78  may have a thickness outside of this range. 
       FIGS. 4 and 5  illustrate a top view and a side view, respectively, of an embodiment of the underwater application system  4 . As illustrated, the underwater application system  4  may be disposed along the streamer  6  that is towed by the survey vessel  10  (e.g., shown on  FIG. 1 ). The underwater application system  4  may at least include a dispensing device  80  in fluid communication with a tank  82  configured to provide the streamer coating  78  (e.g., shown on  FIG. 3 ) to the dispensing device  80 . The dispensing device  80  may be coupled (e.g., welded) to the housing  84  of the SCU  24 . The tank  82  may include any suitable vessel for providing the streamer coating  78 , such as a pressure vessel or pressurized tank. The tank  82  may be hydrodynamically shaped and may be mounted to any portion of the SCU  24 . The SCU  24  may be secured to the underwater application system  4 . For example, the SCU  24  may be secured to the underwater application system  4  via the straps  86 . By of further example, the tank  82  may be coupled or secured to a frame or the housing  84  of the SCU  24  via straps  86  (e.g., made of a polymer) extending around the tank  82  and coupled to the housing  84  via a buckle or ratcheting device  88 , as shown on  FIG. 5 . 
     In some embodiments, the dispensing device  80  includes a plurality of nozzles  90 , as shown on  FIG. 5 . The plurality of nozzles  90  may be configured to direct the streamer coating  78  onto the streamer  6 . The nozzles  90  may be positioned proximate a plurality of cleaning elements such as scrapers  92  of the SCU  24  such that the nozzles  90  may apply the streamer coating after the SCU  24  cleans the streamer  6 . The plurality of scrapers  92  may be coupled to the housing  84 . The plurality of nozzles  90  may be arranged in any suitable configuration. In some embodiments, there may be six or more nozzles  90  arranged around the streamer  6  so that streamer coating  78  (e.g., shown on  FIG. 3 ) may be evenly distributed on streamer  6  (or as evenly as practical). However, in some embodiments, the plurality of the nozzles  90  may include less than six nozzles. In some embodiments, the plurality of nozzles  90  forms multiple rings that are axially offset from each other along an axial direction with respect to the underwater application system  4 . Further, the nozzles  90  may be evenly spaced around the streamer  6  to apply the streamer coating  78  evenly along a circumference of the streamer  6 . However, in some embodiments, the nozzles  90  are unevenly spaced around the streamer  6  to accommodate any streamer components disposed along the streamer  6 . 
     As previously noted, the scrapers  92  may be attached to the housing  84 . In certain embodiments, the scrapers  92  may be disposed along a passage  96  of the underwater application system  4 . As the streamer  6  passes through the passage  96 , the scrapers  92  scrape or remove impurities (e.g., barnacles) from the streamer  6 , and then the nozzles  90  may apply the streamer coating  78  (e.g., shown on  FIG. 3 ) to the streamer  6 . 
     In certain embodiments, the SCU  24  may include guide bars  94  (e.g., streamer guides) to guide the streamer  6  through the passage  96 . The guide bars  94  may be disposed on opposing sides of the passage  96  and may extend along a length of the passage  96 , as shown on  FIG. 4 . The guide bars  94  may be smooth members that taper inward toward the passage  96 . In some embodiments, the guide bars  94  may be disposed on or extend from a first end  98  of the housing  84  of the SCU  24 . The dispensing device  80  may be disposed on a second end  100  of the housing  84  that is opposite to the first end  98 . The guide bars  94  do not restrict rotational movement of the SCU  24  around the streamer  6 . Therefore, in some embodiments, the SCU  24  freely rotates around the streamer  6  as the SCU  24  traverses the length of the streamer  6 . 
     As shown on  FIG. 5 , the tank  82  may include the control system  26  or may be in fluid communication with the control system  26 . The tank  82  may also include an intake or a filler valve  102  to fill the tank  82  with desired substances or mixtures to be dispensed (e.g., the streamer coating  78 ). The control system  26  may be placed downstream of the tank  82  (e.g., the inlet  62  of the control system  26  may pass contents of the tank  82  through the control system  26 ) and may release pressurized contents contained within the tank  82  via the outlet  64  of the control system  26  and a conduit  104  (e.g., a fluid connection) extending from the control system  26  to the dispensing device  80 . In some embodiments, the tank  82  may be configured to receive an amount of streamer coating configured to coat an entire axial length of the streamer. Further, the tank  82  may be filled with compressed gas via the filler valve  102 . In some embodiments, the tank  82  includes an additional air filler valve  105 , such that pressurized gas and the streamer coating  78  may be input into the tank  82  via separate valves. 
     The tank  82  may contain the streamer coating  78  which may include thermoplastic polymers, such as polyurethane, polypropylene, polyamides, waxes, and combinations thereof. In some embodiments, the streamer coating  78  may be a wax composition that includes wax and one or more additional materials, such as a solvent. By way of example, the wax composition may comprise lanolin wax and lanolin alcohol. Suitable solvents may include alcohols and oleaginous fluids. Non-limiting examples of suitable oleaginous liquids may include organic oils (e.g., vegetable oils) or synthetic oils. Suitable waxes may include, but are not limited to, animal waxes, plant waxes, petroleum waxes, polyethylene waxes, and combinations thereof. Animal waxes may include waxes synthesized by animals (including insects) as well as chemically modified versions thereof. Plant waxes may include waxes synthesized by plants as well as chemically modified versions thereof. Petroleum waxes may include waxes derived from petroleum. Polyethylene waxes may include waxes derived from polyethylene. Specific examples of suitable waxes may include, but are not limited to, cocoa butter, illipe butter, lanolin, cetyl palmitate, bayberry wax, lanolin alcohol, paraffin wax, silicone wax, and sumax wax, among others. The wax composition may be selected with a melting point that is around water temperature. In some embodiments, the wax composition may have a melting point within about 2° C., about 5° C., or about 10° C. of water temperature. In certain embodiments, the tank  82  may also include pressurized gas to propel contents from the tank  82  and out through the dispensing device  80  onto the streamer  6 . The pressurized gas may include air, nitrogen, or carbon dioxide, or other suitable gas. One of ordinary skill in the art with the benefit of this disclosure should be able to determine an appropriate gas to use for a particular application. 
       FIG. 6  illustrates a top view of the underwater application system  4  including a plurality of tanks  82  fluidly coupled to the dispensing device  80  via conduits  104 , in accordance with some embodiments of the present disclosure. As illustrated, the underwater application system  4  may include a first tank  82  and a second tank  82 , each tank configured to contain a mixture of compressed gas and the streamer coating  78  (e.g., shown on  FIG. 3 ). The pressure in the tanks  82  may exceed an ambient water pressure (e.g., indicated by the directional arrow  60 , shown on  FIG. 2A ). In some embodiments, the first tank  82  may contain the compressed gas and the second tank  82  may contain the streamer coating  78 , and the contents may mix in the dispensing device  80  before being dispensed onto the streamer  6 . In other embodiments, a gas contained in the first tank  82  could be utilized to expel a fluid in the second tank  82 . 
       FIG. 7  illustrates a cross-sectional view of the dispensing device  80  including brush applicators  106 , in accordance with some embodiments of the present disclosure. In some embodiments, the brush applicators  106  may be disposed at least partially over respective nozzles of the plurality of nozzles  90 . In some embodiments, the dispensing device  80  may include any device (e.g., roller, sponge, etc.) suitable for applying the streamer coating  78  (e.g., shown on  FIG. 3 ). The streamer coating  78  may be provided to the brush applicators  106  via the plurality of nozzles  90 . The brush applicators  106  may be configured to rotate about a central axis of the streamer  6 . In some embodiments, two or more brush applicators  106  may be positioned around the circumference of the streamer  6 . The brush applicators  106  may contact the streamer  6  as the underwater application system  4  (e.g., shown on  FIGS. 4 and 5 ) moves along the streamer  6 . Further, as the underwater application system  4  moves, the streamer  6  may pass through an arrangement of the brush applicators  106  after the SCU  24  (e.g., shown on  FIG. 5 ) has cleaned the streamer  6 . The brush applicators  106  may be configured to rotate about the streamer  6  while applying the streamer coating  78  to the streamer  6 . 
     The underwater application system  4  may further include a mounting bracket  108 . The dispensing device  80  including the nozzles  90  and/or the brush applicators  106  may be mounted to the mounting bracket  108 . The mounting bracket  108  may be coupled to a portion of the SCU  24  along the passage  96  such that the streamer  6  is scraped with the scrapers  92  before being sprayed by the dispensing device  80  as the underwater application system  4  receives the streamer  6  within the passage  96  as the underwater application system  4  moves along the streamer  6 , as shown on  FIGS. 4 and 5 , for example. In some embodiments, the mounting bracket  108  has a circular shape such that the plurality of nozzles  90  mounted to the mounting bracket  108  may form a ring around the streamer  6 . The mounting bracket  108  may include a hinge  110  that is configured to open and close the mounting bracket  108  for installation purposes. In some embodiments, the SCU  24  and the underwater application system  4  may be mounted on or movably disposed on or around the streamer  6  after a proximal end of the streamer  6  is coupled to the survey vessel  10  (e.g., as shown on  FIG. 1 ). Further, a distal end of the streamer  6  may be deployed in the water  14  at a distance from the survey vessel  10  such that the mounting bracket  108  having the circular shape may not be threaded over either the proximal or distal end of the streamer  6 . As such, the hinge  110  may open the mounting bracket  108  such that the mounting bracket  108  may slide onto the streamer  6  along any portion of the streamer  6 . After the mounting bracket  108  slides onto the streamer  6 , the hinge  110  may close the mounting bracket  108  such that the mounting bracket  108  is closed around the streamer  6 . However, in some embodiments, the mounting bracket  108  may be fixed such that the mounting bracket  108  does not hinge open. Instead, the mounting bracket  108  may have an opening  112  at least as wide as a diameter of the streamer  6  such that the mounting bracket  108  may slide onto the streamer  6  via the opening  112 . In such embodiments, coupling the mounting bracket  108  to the SCU  24  may hold the mounting bracket  108  in place (e.g., around the streamer  6 ) with respect to the streamer  6  during operation. 
       FIG. 8  illustrates an exemplary flow chart depicting an operative sequence of the underwater application system  4  (e.g., shown on  FIG. 5 ), in accordance with some embodiments of the present disclosure. At step  114 , in some embodiments, the underwater application system  4  and the SCU  24  may be initially disposed underwater at a proximal end of the streamer  6  or between a rear or stern of the survey vessel  10  and a first geophysical sensor  8 , as shown on  FIG. 1 . At step  116 , in some embodiments, the underwater application system  4  and the SCU  24  may move along the streamer  6  through the body of water  14 , as the survey vessel  10  tows the streamer  6 , as shown on  FIG. 1 . At step  118 , in some embodiments, water pressure may increase above a threshold value, due to a speed and/or direction of the survey vessel  10  and/or a tow depth. The water pressure, upon reaching the threshold limit, may cause the control system  26  to open to dispense the streamer coating  78  onto the streamer  6 . At step  120 , in some embodiments, the underwater application system  4  and the SCU  24  may traverse the entire length of the streamer  6  scraping and then applying the streamer coating  78  (e.g., shown on  FIG. 3 ) to the streamer  6  until the underwater application system  4  and the SCU  24  reach the distal end of the streamer  6  that is opposite to the proximal end of the streamer  6  that is attached to the survey vessel  10 , as shown on  FIG. 1 , for example. 
     As the water pressure decreases below the threshold, due to a slower speed and/or a change of direction of the survey vessel  10  and/or a shallower tow depth, the valve  28  may close to prevent application of the streamer coating  78 . Therefore, as set forth above, the underwater application system may be activated based on movement, speed, and/or a depth of the underwater application system  4  along the streamer  6 . Activating the underwater application system  4  may include actuating the valve  28  of the underwater application system  4 . In some embodiments, the valve  28  is configured to open while the underwater application system  4  is moving, and close when the underwater activation system  4  stops moving. In another embodiment, the valve  28  may be configured to remain open after the underwater application system  4  starts moving. 
     Further, as set forth above in some embodiments, the underwater application system  4  may be coupled to the SCU  24 . The SCU  24  may include any suitable device or cleaning elements for removing marine growth from the streamers  6 . In one embodiment, the SCU  24  is configured to remove the marine growth from the streamers  6  using scrapers  92  (e.g., shown on  FIG. 5 ) prior to application of the streamer coating  78  (e.g., shown on  FIG. 3 ). The SCU  24  may be configured to move along a streamer  6  along an axial direction. In some embodiments, the SCU  24  may be configured to rotate freely about the streamer  6 . 
     Although specific embodiments have been described above, these embodiments are not intended to limit the scope of the present disclosure, even where only a single embodiment is described with respect to a particular feature. Examples of features provided in the disclosure are intended to be illustrative rather than restrictive unless stated otherwise. The above description is intended to cover such alternatives, modifications, and equivalents as would be apparent to a person skilled in the art having the benefit of this disclosure. 
     The scope of the present disclosure includes any feature or combination of features disclosed herein (either explicitly or implicitly), or any generalization thereof, whether or not it mitigates any or all of the problems addressed herein. Various advantages of the present disclosure have been described herein, but embodiments may provide some, all, or none of such advantages, or may provide other advantages.