Patent Description:
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.

<CIT> describes methods to preserve or restore the low roughness throughout an outer shell of a device ( e.g. a streamer) used underwater for seismic surveys, by applying various substances that fill micro-cracks, are easy to polish or are self-healing. Apparatuses used to implement these methods may be used shortly before the devices are deployed in water, for example, having the device passing through such an apparatus as it is moved to be deployed in water.

<CIT> describes a streamer-preparation apparatus that cleans a geophysical cable to prepare it for application of an antifouling paint. An embodiment discloses a method comprising: moving a streamer into position for cleaning; directing a cleaning fluid onto the streamer as the streamer is being moved; and directing a gaseous fluid onto the streamer as the streamer is being moved. Another embodiment discloses: applying an antifouling paint to the streamer with the streamer-preparation apparatus; and applying a curing agent to the streamer with the streamer-preparation apparatus.

A further example of a cable preparation device is described in <CIT>.

The invention provides for a marine geophysical survey system according to claim <NUM>, and a method of performing a geophysical survey operation according to claim <NUM>.

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.

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. 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.

Embodiments relate generally to marine geophysical surveying. More particularly, embodiments relate to a wax application system for application of a wax coating to a surface of a streamer. The wax coating can be at a solid or semi-solid state at room temperature (approximately <NUM>° C). The wax coating may protect the streamer by preventing marine growth, which would otherwise negatively interfere with streamer operation. Accordingly, by application of the wax coating, operation of the streamer in marine surveying may be improved.

Referring now to <FIG>, marine geophysical survey system <NUM> that employs wax application system <NUM> is illustrated in accordance with embodiments of the disclosure. As will be discussed in more detail below, in some embodiments, wax application system <NUM> may be operable to apply a wax coating (e.g., wax coating <NUM> shown on <FIG>) to streamer <NUM>. Streamer <NUM> may include a long cable (or other elongated structure) on which geophysical sensors <NUM> may be disposed at spaced apart locations along the length of streamer <NUM>. In another embodiment, survey vessel <NUM> may include a plurality of wax application systems <NUM> operable to apply the wax coating to a plurality of streamers <NUM>.

In the illustrated embodiment, marine geophysical survey system <NUM> may include survey vessel <NUM> on which wax application system <NUM> may be employed. Survey vessel <NUM> may move along surface <NUM> of body of water <NUM>, such as a lake or ocean. Survey vessel <NUM> may include thereon equipment, shown generally at <NUM> and collectively referred to herein as a "recording system. " Recording system <NUM> may include 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 <NUM> (explained further below) and for actuating energy source <NUM> at selected times. Recording system <NUM> may also include devices (none shown separately) for determining the geodetic position of survey vessel <NUM> and various geophysical sensors <NUM>.

In some embodiments, survey vessel <NUM> or another vessel may tow at least one streamer <NUM> on which geophysical sensors <NUM> may be disposed. As illustrated, energy source <NUM> and streamer <NUM> may be towed above water bottom <NUM>. Streamer <NUM> may be a towed marine seismic streamer, a towed marine electromagnetic streamer, or a combination thereof. While not shown, some marine seismic surveys locate geophysical sensors <NUM> on ocean bottom cables or nodes in addition to, or instead of, streamer <NUM>. As illustrated, geophysical sensors <NUM> may be disposed at spaced apart locations on streamer <NUM>. Geophysical sensors <NUM> may be, without limitation, seismic sensors such as geophones, hydrophones, or accelerometers, or electromagnetic field sensors, such as electrodes or magnetometers. Geophysical sensors <NUM> may generate response signals, such as electrical or optical signals, in response to detecting energy emitted from energy source <NUM> after the energy has interacted with formations <NUM> below water bottom <NUM>. In some embodiments, more than one streamer <NUM> may be towed by survey vessel <NUM> or another vessel, and streamers <NUM> 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.

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 (i.e. by equipment on a vessel) or onshore (i.e. 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, wax application system <NUM> may be located on survey vessel <NUM>. As illustrated, wax application system <NUM> may be located at or near stern <NUM> of survey vessel <NUM> so that wax application system <NUM> may be proximate streamer <NUM> during its deployment into, or recovery from, body of water <NUM>. During recovery and/or deployment, marine growth may be scraped, or otherwise removed, to prepare streamer <NUM> for application of the wax coating. In some embodiments, a major portion of the marine growth may be removed from streamer <NUM> during its recovery onto survey vessel <NUM>. During subsequent deployment of streamer <NUM> into body of water <NUM>, the wax coating may be applied to streamer <NUM>. The wax coating may be applied by applying a wax to streamer <NUM> using any suitable technique, including, but not limited to, spray coating, drip coating, or solid application. Prior to application of the wax coating, embodiments may include cleaning and drying streamer <NUM> to prepare the surface of streamer <NUM> for the wax coating.

Referring now to <FIG>, an embodiment of wax application system <NUM> is illustrated in more detail. It should be appreciated that while the below description of wax application system <NUM> is applicable to application of wax in a liquid state, embodiments may also be used that apply wax in a solid or semi-solid state. In the illustrated embodiment, wax application system <NUM> comprises wax reservoir <NUM>, temperature control system <NUM>, pump <NUM>, applicator conduit <NUM>, and wax applicator <NUM>. Wax application system <NUM> may be operable to deliver wax contained in wax reservoir <NUM> to wax applicator <NUM> for application of a wax coating to streamer <NUM> and/or streamer components <NUM>. The wax coating may be applied while streamer <NUM> is being deployed into body of water <NUM> (e.g., shown on <FIG>). The wax coating may also be applied to streamer components <NUM> that may not be stored with streamer <NUM> on survey vessel <NUM> and, instead, are attached to streamer <NUM> during deployment. Examples of streamer components <NUM> may include positioning and navigation control devices (e.g., birds) with one or more surfaces for positioning streamer <NUM>, retrievers, and other modules. Additional examples of streamer components <NUM> may include, but are not limited to acoustic pingers, external compasses, and external protective coverings, among others.

In the embodiment of <FIG>, wax reservoir <NUM> may store a wax. Wax reservoir <NUM> may be any suitable container for storing the wax. The wax may be stored in wax reservoir <NUM> in a solid or semi-solid state, for example. The wax may generally be in a solid (or semi-solid) state at room temperature (approximately <NUM>° C). Suitable waxes should adhere to surfaces of streamer <NUM> when sprayed or otherwise applied to streamer <NUM>. If applied in a liquid or semi-solid state, the wax should readily transition into a solid state to form a wax coating in a solid state on streamer <NUM>. In some embodiments, the wax can form the wax coating in a solid state prior to entry of streamer <NUM> into body of water <NUM> (e.g., shown on <FIG>). In this manner, the wax coating should adhere to streamer <NUM> and not be readily washed off as streamer <NUM> is towed, as waxes are typically insoluble in water. Suitable waxes should have a melting point that is greater than the temperature of body of water <NUM>, referred to herein as "water temperature. " In some embodiments, the wax may have a melting point that is equal to or exceeds the water temperature. In some embodiments, the wax may have a melting point that is equal to or exceeds the water temperature by at least about <NUM>° C. In some embodiments, the wax may have a melting point that exceeds the water temperature by about <NUM>° C to about <NUM>° C. In some embodiments the wax may have a melting point that does not exceed the temperature of the water by more than a predetermined amount. If the melting point is too low, the wax coating can soften and prematurely be washed off of streamer <NUM>. Alternatively, if the melting point is too high, the wax coating can be too brittle and not be capable of withstanding the stresses associated with towing. 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. One of ordinary skill in the art, with the benefit of this disclosure, should be able to select a suitable wax based, for example, on melting point, among other factors.

Wax application system <NUM> may also include temperature control system <NUM>. Temperature control system <NUM> may include one or more heating elements to heat the wax in wax reservoir <NUM> to above its melting point so that the wax can be delivered from wax reservoir <NUM> to wax applicator <NUM>. In some embodiments, temperature control system <NUM> may heat the wax in wax reservoir <NUM> to a temperature of about <NUM> or greater. This temperature may also be maintained in wax reservoir <NUM> so that the wax remains in a liquid state. In some embodiments, temperature control system <NUM> not only controls the temperature of the wax in wax reservoir <NUM>, but can also control the temperature of the wax in applicator conduit <NUM> and wax applicator <NUM>, for example, to prevent (or reduce) the wax prematurely transitioning to a solid state after it exits wax reservoir <NUM>, but prior to its application onto streamer <NUM>. By way of example, temperature control system <NUM> may be operable to maintain the temperature of the wax in applicator conduit <NUM> and/or wax applicator <NUM> above its melting point. In some embodiments, temperature control system <NUM> may also include humidity control, including, one or more sensors, to monitor humidity in wax application system <NUM>. Humidity may be monitored in wax reservoir <NUM>, applicator conduit <NUM>, and/or wax applicator <NUM>. The humidity control may be operable to add or remove water from the air in wax application system <NUM>. In embodiments, the melting point of the wax can be adjusted in response to a change in the temperature of the water into which streamer <NUM> is to be deployed. For example, if vessel <NUM> moves from warmer water to cooler water, temperature control system <NUM> can adjust additives or the mix ratio of the wax so that the wax will have a melting point at a predetermined temperature above the temperature of the water. In embodiments, the wax can be selected in advance to have a melting point at or above an expected water temperature. By of example, the wax may be selected to have a melting point that is equal to or exceeds the water temperature. In some embodiments, the wax may be selected to have a melting point that does not exceed the temperature of the water by more than a predetermined amount. In some embodiments, the water temperature may be measured and then the wax may be selected to have a melting point that does not exceed the temperature of the water by more than a predetermined amount. The predetermined amount may range, for example, from about <NUM>° C to about <NUM>° C.

Pump <NUM> may be operable to move the wax from wax reservoir <NUM> to wax applicator <NUM>, for example, by way of applicator conduit <NUM>. Pump <NUM> may include any of a variety of suitable pumps, including, but not limited to, centrifugal and positive displacement pumps, suitable for moving the wax. While <FIG> illustrates use of pump <NUM>, it should be understood that, in some embodiments, wax reservoir <NUM> may be arranged so that the wax can be delivered to pump applicator <NUM> by gravity feed instead of pump <NUM> or by gravity feed in combination with pump <NUM> to provide desired quantities of the wax.

Wax applicator <NUM> may be operable to apply a wax coating onto streamer <NUM> and/or streamer components <NUM>. Wax applicator <NUM> may include nozzles (e.g., nozzles <NUM> shown on <FIG> and <FIG>) or other suitable device for application of the wax to streamer <NUM> and/or streamer components <NUM>. Suitable techniques for application of the wax may include, but are not limited to, spraying, brushing, rubbing, blowing, or dripping. In some embodiments, the wax applicator <NUM> may spray the wax in a liquid state onto streamer <NUM> and/or streamer components <NUM>, for example, to form a wax coating. The wax may then be allowed to transition from liquid (or semi-solid) to a solid phase on the streamer <NUM> and/or streamer components <NUM>. To avoid premature removal of the wax, in particular embodiments, the wax should transition from the solid state prior to entry of streamer <NUM> into body of water <NUM> (e.g., shown on <FIG>). Wax applicator <NUM> may independently control the amount of wax applied to streamer <NUM> so that the thickness of wax coating may be independent of the speed streamer <NUM> passes through wax applicator <NUM>. For the streamer components <NUM> that are removed from streamer <NUM> for storage, the wax may be applied to streamer components <NUM> and then allowed to transition to a solid. The streamer components <NUM> with a wax coating may then be attached to streamer <NUM> as streamer <NUM> is deployed into body of water <NUM>.

<FIG> illustrates streamer <NUM> with wax coating <NUM> in more detail. As previously described wax coating <NUM> may be applied to streamer <NUM> during deployment into body of water <NUM> (e.g., shown on <FIG>). Wax coating <NUM> may include a wax that has dried into a solid state. In the illustrated embodiment, wax coating <NUM> may also be applied to streamer components <NUM>, such as position control devices <NUM> that include one or more wings <NUM>. Wax coating <NUM> may have any suitable thickness based on a number of factors, including, but not limited to, water temperature, type of wax, and deployment time. In some embodiments, wax coating <NUM> may have a thickness of about <NUM> millimeters to about <NUM> millimeter. It should be understood that the present embodiments should not be limited to the disclosed range for thickness of wax coating <NUM>, but rather, in some embodiments, wax coating <NUM> may have a thickness outside this range.

<FIG> illustrates an embodiment of wax application system <NUM> disposed on survey vessel <NUM>. As illustrated, wax application system <NUM> may be disposed on stern <NUM> of survey vessel <NUM>. In the illustrated embodiment, streamer <NUM> may be stored on drum <NUM>. Streamer <NUM> may be unwound from drum <NUM> and deployed in body of water <NUM> (e.g., shown on <FIG>). In some embodiments, spooling block <NUM> (e.g., a Neilsen block) or other suitable device may be used to aid in deployment of streamer <NUM> from drum <NUM>. In the illustrated embodiment, streamer <NUM> may be deployed in the direction indicated by arrow <NUM>.

As illustrated, streamer <NUM> may pass through wax applicator <NUM> prior to deployment. In the illustrated embodiment, wax applicator <NUM> may be positioned on survey vessel <NUM> such that spooling block <NUM> is disposed between wax applicator <NUM> and drum <NUM>; however, other suitable locations for wax applicator <NUM> may be used depending, for example, on the particular application. As previously described, wax applicator <NUM> may apply wax coating <NUM> (e.g., shown on <FIG>) to streamer <NUM>. Wax may be supplied to wax applicator <NUM> from wax reservoir <NUM> by way of applicator conduit <NUM>. Temperature control system <NUM> may heat the wax and maintain the wax in a liquid state. Pump <NUM> may be used to deliver the wax from wax reservoir <NUM> to wax applicator <NUM> by way of applicator conduit <NUM>. While wax reservoir <NUM>, temperature control system <NUM>, and pump <NUM> are shown on stern <NUM> of survey vessel <NUM>, it is not necessary for these components of wax application system <NUM> to be disposed on stern <NUM>, and they can be disposed on survey vessel <NUM> in another suitable location depending, for example, on the particular arrangement of survey vessel <NUM>.

In some embodiments, wax applicator <NUM> may direct wax in a liquid state onto streamer <NUM> to form wax coating <NUM> (e.g., shown on <FIG>). After its application, wax coating <NUM> may transition to a solid state so that it should not be readily removed after deployment. As illustrated, wax applicator <NUM> may include a nozzle unit <NUM> for application of the wax. Nozzle unit <NUM> may include nozzles <NUM> for directing the wax onto the streamer <NUM>. Nozzles <NUM> may be arranged in nozzle unit <NUM> in any suitable configuration. In some embodiments, there may be three or more of nozzles <NUM> arranged around streamer <NUM> so that wax may be evenly distributed on streamer <NUM> (or as evenly as practical). In a particular embodiment, the nozzles <NUM> may be airless nozzles in which air is not injected into the wax. Airless nozzles may be used, for example, to prevent premature cooling of the wax before it is applied to streamer <NUM>. In some embodiments, nozzle unit <NUM> may be enclosed with nozzles <NUM> disposed in nozzle unit <NUM>. For example, nozzle unit <NUM> may be in the form of a spray chamber. The streamer <NUM> may pass through the nozzle unit <NUM> with the nozzles <NUM> applying the wax to the streamer <NUM> in the nozzle unit <NUM>. The air in the nozzle unit <NUM>, in these embodiments, may be heated, for example, to prevent the wax from transforming to the solid state after leaving the nozzles <NUM> but prior to contacting the streamer <NUM>. The applicator conduit <NUM> may also be heated to maintain the wax in a liquid state.

In some embodiments, wax applicator <NUM> may further include a device, such as a streamer positioning assembly <NUM>, for holding wax applicator <NUM> on streamer <NUM> while allowing streamer <NUM> to pass there through. Streamer positioning assembly <NUM> may also position nozzles <NUM> at a fixed distance from streamer <NUM>. Streamer positioning assembly <NUM> may include wheels <NUM> (e.g., castors or rollers) or other suitable devices, such as belts or continuous tracks, that grip streamer <NUM> and apply a slight compression force. In the illustrated embodiment, streamer positioning assembly <NUM> includes two sets of wheels <NUM>. Streamer positioning assembly <NUM> may be configured to open while applying the compression force to ensure that wax applicator <NUM> both follows inconsistencies in streamer diameter and positions nozzles <NUM> concentrically (or as concentrically as practical) around streamer <NUM>. Streamer positioning assembly <NUM> may be configured to open sufficiently to allow streamer attachments to pass through. In the illustrated embodiments, streamer positioning assembly <NUM> is positioned before nozzles <NUM> with respect to direction (indicated by arrow <NUM>) of movement of streamer <NUM>.

Cleaning unit <NUM> may also be disposed on survey vessel <NUM>. Where used, cleaning unit <NUM> may be operable, for example, to prepare streamer <NUM> for application of the wax. As illustrated, cleaning unit <NUM> may be disposed between spooling block <NUM> and drum <NUM>; however, other locations for cleaning unit <NUM> may also be suitable depending, for example, on the particular application. Cleaning unit <NUM> may include a fluid application unit <NUM> and a drying unit <NUM>. Fluid application unit <NUM> may include fluid nozzles <NUM> operable to apply a cleaning fluid onto streamer. Cleaning fluid may include any suitable fluid for cleaning streamer <NUM>, such as air and water (e.g., freshwater, seawater). In some embodiments, the water may include hot water that has been heated to a temperature greater than ambient temperature. Drying unit <NUM> may include gas nozzles <NUM> operable to apply a gaseous fluid, such as air, onto streamer <NUM>. The gaseous fluid may blow off the cleaning fluid from streamer <NUM> so that the cleaning fluid does not dry on streamer <NUM>. In other embodiments, the gaseous fluid may dry the cleaning fluid on streamer <NUM>. In some embodiments, the gaseous fluid may be passed through an air drier to remove moisture from the air prior to directing the gaseous fluid onto the streamer <NUM>. Cleaning unit <NUM> may further include a device, such as cleaning unit positioning assembly <NUM>, for holding cleaning unit <NUM> on streamer <NUM> while allowing streamer <NUM> to pass there through. Cleaning unit positioning assembly <NUM> may also position fluid nozzles <NUM> and gas nozzles <NUM> at a fixed distance from streamer <NUM>. Cleaning unit positioning assembly <NUM> may include cleaning unit wheels <NUM> (e.g., castors or rollers), or continuous tracks that grip streamer <NUM> and apply a slight compression force on streamer <NUM>. While not shown, an optional device may be used to mechanically remove barnacles or other marine growth from streamer <NUM> before entering cleaning unit <NUM>. The device may be positioned on the inboard side of cleaning unit <NUM>, for example, between cleaning unit <NUM> and drum <NUM>. The device may use any suitable mechanism for mechanically removing marine growth, including, but not limited to, scrapers.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM>, supplemental wax reservoir <NUM>, wax applicator <NUM>, and/or heating chamber <NUM>. Wax reservoir <NUM> may contain wax <NUM>. Wax <NUM> in wax reservoir <NUM> may be heated so that at least a portion of wax <NUM> transitions to a liquid state (or semi-solid state), for example, to facilitate application onto streamer <NUM>. Any suitable technique may be used for heating wax <NUM>, including, but not limited to, temperature control system <NUM> (e.g., shown on <FIG> and <FIG>), as previously described. Wax <NUM> that has been heated to a liquid or semi-solid state may be fed from wax reservoir <NUM> to supplemental wax reservoir <NUM> by way of supply conduit <NUM>. Pump <NUM> may be operable to deliver wax <NUM> from supplemental wax reservoir <NUM> to wax applicator <NUM>. As illustrated, pump <NUM> may deliver wax <NUM> to wax applicator <NUM> via applicator conduit <NUM>. While <FIG> illustrates delivery of wax <NUM> to wax applicator <NUM> from supplemental wax reservoir <NUM>, it is contemplated that pump <NUM> or other suitable mechanisms may deliver wax <NUM> directly from wax reservoir <NUM> to wax applicator <NUM>. In some embodiments, applicator conduit <NUM> may be heated, for example, to prevent wax <NUM> from prematurely transitioning to a solid state.

Wax applicator <NUM> may direct wax <NUM> onto streamer <NUM> to form wax coating <NUM>. Streamer <NUM> may pass through wax applicator <NUM> in the direction indicated by arrow <NUM>. Wax applicator <NUM> may include a wax application device <NUM> in contact with streamer <NUM> for receiving wax <NUM> from applicator conduit <NUM> and applying wax <NUM> to streamer <NUM>. Wax application device <NUM> may include any suitable device for applying wax <NUM>, including, but not limited to, brushes, rollers (e.g., rollers <NUM> shown on <FIG>), or sponges. As illustrated, multiple wax application devices <NUM> may be disposed around the circumference of streamer <NUM> for more uniform application of wax <NUM> onto streamer <NUM>. Wax application device <NUM> may direct wax <NUM> (e.g., in a liquid or semi-solid state) onto streamer <NUM> to form wax coating <NUM> (e.g., shown on <FIG>). After its application, wax coating <NUM> may transition to a solid state so that it should not be readily removed after deployment. In some embodiments, heating chamber <NUM> may receive streamer <NUM> after application of wax coating <NUM>. Heating chamber <NUM> may heat wax coating <NUM> after its application onto streamer <NUM>, for example, to soften wax coating <NUM> so that wax coating <NUM> can be more evenly distributed on streamer <NUM>. Heating chamber <NUM> may use any suitable technique for heating, including heated air.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM>, supplemental wax reservoir <NUM>, wax applicator <NUM>, and heating chamber <NUM>. Wax reservoir <NUM> may contain wax <NUM>. Wax <NUM> in wax reservoir <NUM> may be heated so that at least a portion of wax <NUM> transitions to a liquid state (or semi-solid state). Any suitable technique may be used for heating wax <NUM>, including, but not limited to, temperature control system <NUM> (e.g., shown on <FIG> and <FIG>), as previously described. Wax <NUM> may be fed from wax reservoir <NUM> to supplemental wax reservoir <NUM> by way of supply conduit <NUM>. Pump <NUM> may be operable to deliver wax <NUM> from supplemental wax reservoir <NUM> to wax applicator <NUM>. As illustrated, pump <NUM> may deliver wax <NUM> to wax applicator <NUM> via applicator conduit <NUM>. While <FIG> illustrates delivery of wax <NUM> to wax applicator <NUM> from supplemental wax reservoir <NUM>, it is contemplated that pump <NUM> or other suitable mechanisms may deliver wax <NUM> directly from wax reservoir <NUM> to wax applicator <NUM>. In some embodiments, applicator conduit <NUM> may be heated, for example, to prevent wax <NUM> from prematurely transitioning to a solid state.

Wax applicator <NUM> may direct wax <NUM> onto streamer <NUM> to form wax coating <NUM>. Streamer <NUM> may pass through wax applicator <NUM> in the direction indicated by arrow <NUM>. As illustrated, wax applicator <NUM> may include rollers <NUM> in contact with streamer <NUM> for receiving wax <NUM> from applicator conduits <NUM> and applying wax <NUM> to streamer <NUM>. As illustrated, multiple rollers <NUM> may be disposed around the circumference of streamer <NUM> for more uniform application of wax <NUM> onto streamer <NUM>. Wax <NUM> may be applied onto the circumference of rollers <NUM> and then onto streamer <NUM>. Rollers <NUM> may direct wax <NUM> (e.g., in a liquid or semi-solid state) onto streamer <NUM> to form wax coating <NUM> (e.g., shown on <FIG>). After its application, wax coating <NUM> may transition to a solid state so that it should not be readily removed after deployment. In some embodiments, heating chamber <NUM> may receive streamer <NUM> after application of wax coating <NUM>. Heating chamber <NUM> may heat wax coating <NUM> after its application onto streamer <NUM>, for example, to soften wax coating <NUM> so that wax coating <NUM> can be more evenly distributed on streamer <NUM>. Heating chamber <NUM> may use any suitable technique for heating, including heated air.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM>, overflow reservoir <NUM>, and recirculating pump <NUM>. Wax reservoir <NUM> may contain wax <NUM> that has been heated to a liquid state (or semi-solid state). Wax reservoir <NUM> may comprise a streamer inlet <NUM> and a streamer outlet <NUM>. Streamer inlet <NUM> may receive streamer <NUM>. The streamer <NUM> may pass through wax <NUM> in wax reservoir <NUM>, exiting by way of streamer outlet <NUM>. Streamer <NUM> may pass through wax <NUM> in the direction indicated by arrow <NUM>. As streamer <NUM> passes through wax <NUM>, wax <NUM> may adhere to streamer <NUM> forming wax coating <NUM>. After its application, wax coating <NUM> may transition to a solid state so that it should not be readily removed after deployment. As illustrated, overflow reservoir <NUM> may be disposed under streamer <NUM> to receive wax <NUM> from wax reservoir <NUM> that may spill during application onto streamer <NUM>. Recirculating pump <NUM> may be in fluid communication with wax reservoir <NUM> and overflow reservoir <NUM>. Recirculating pump <NUM> may pump wax <NUM> from overflow reservoir <NUM> back into wax reservoir <NUM>.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM>, wax removal unit <NUM>, and/or heating chamber <NUM>. Wax reservoir <NUM> may contain wax <NUM> (e.g., in a liquid or semi-solid state) that has been heated to a liquid state. Wax <NUM> may be delivered onto a streamer <NUM> by way of applicator conduit <NUM>. In the illustrated embodiment, applicator conduit <NUM> may include an exit port <NUM> proximate streamer <NUM>. Streamer <NUM> may pass by applicator conduit <NUM> in the direction indicated by arrow <NUM>. Applicator conduit <NUM> may be in fluid connection with wax reservoir <NUM>. In some embodiments, applicator conduit <NUM> may receive wax <NUM> from wax reservoir <NUM> and deliver wax <NUM> onto streamer <NUM> with wax <NUM> pouring from exit port <NUM> of applicator conduit <NUM> onto streamer <NUM> as streamer <NUM> passes by the exit port <NUM>. Wax <NUM> may flow around the circumference of streamer <NUM> forming wax coating <NUM>. After its application, wax coating <NUM> may transition to a solid state so that it should not be readily removed after deployment. In some embodiments, wax application system <NUM> may further include wax removal unit <NUM> for removal of excess wax <NUM> from streamer <NUM>. Wax removal unit <NUM> may include scrapers, sponges, brushes, or suitable devices that can remove wax <NUM> from streamer <NUM>. In some embodiments, heating chamber <NUM> may receive streamer <NUM> after application of wax coating <NUM>. Heating chamber <NUM> may heat wax coating <NUM> after its application onto streamer <NUM>, for example, to soften wax coating <NUM> so that wax coating <NUM> can be more evenly distributed on streamer <NUM>. Heating chamber <NUM> may use any suitable technique for heating, including heated air.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM> and wax applicator <NUM>. Wax reservoir <NUM> may contain wax <NUM> (e.g., in a liquid or semi-solid state) that has been heated to a liquid state. Wax <NUM> may be delivered onto streamer <NUM> by way of wax applicator <NUM>. Wax <NUM> may be gravity fed to wax applicator <NUM>. Wax <NUM> may flow on wax applicator <NUM> to contact surface <NUM> in engagement with streamer <NUM>. Streamer <NUM> may pass through wax applicator <NUM> in the direction indicated by arrow <NUM> so that wax <NUM> may be transferred from contact surface <NUM> to streamer <NUM>, forming wax coating <NUM>. To ensure sufficient distribution of wax <NUM> on streamer <NUM>, in some embodiments, contact surface <NUM> may be in contact with streamer <NUM> around the entire circumference of streamer <NUM>. In some embodiments, wax applicator <NUM> may be heated to maintain wax <NUM> in the liquid state (or semi-solid state), for example, enabling removal of excess wax <NUM> and a desired surface finish. Wax applicator <NUM> may be made from any suitable material, including but not limited to, metals or polymers. Wax applicator <NUM> may include internal conduits <NUM> for even distribution of wax <NUM> onto contact surface <NUM> in engagement with streamer <NUM>. Wax <NUM> may pass through internal conduits <NUM>. In some embodiments, wax applicator <NUM> may be spring loaded, for example, with spring mechanism <NUM> applying force in direction indicated by arrows <NUM> pressing contact surface <NUM> into engagement with streamer <NUM>.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM> and wax applicator <NUM>. Wax reservoir <NUM> may contain wax <NUM> that has been heated to a liquid state (or semi-solid state). Wax <NUM> may be delivered onto a streamer <NUM> by way of applicator <NUM>. Wax <NUM> may be gravity fed to wax applicator <NUM> or alternatively fed by application of force, indicated by arrow <NUM>. Wax applicator <NUM> may be in contact with streamer <NUM>. Wax <NUM> may flow through wax applicator <NUM> and be transferred to streamer <NUM>, forming wax coating <NUM>. As illustrated, wax applicator <NUM> may comprise sponge <NUM> through which wax <NUM> may pass. Wax <NUM> may flow on wax applicator <NUM> to contact surface <NUM> in engagement with streamer <NUM>. Streamer <NUM> may pass through wax applicator <NUM> so that wax <NUM> may be transferred through sponge <NUM> to streamer <NUM> to form wax coating <NUM>. To ensure sufficient distribution of wax <NUM> on streamer <NUM>, in some embodiments, sponge <NUM> may be disposed around the entire circumference of streamer <NUM>. In some embodiments, wax applicator <NUM> may be heated to maintain wax <NUM> in the liquid state, for example, enabling removal of excess wax <NUM> and a desired surface finish. As illustrated, wax reservoir <NUM> and wax applicator <NUM> may be disposed in a heating chamber <NUM>. In some embodiments, heating chamber <NUM> may receive streamer <NUM> so that streamer <NUM> may enter heating chamber <NUM>, pass through sponge <NUM> in heating chamber <NUM>, and then exit heating chamber <NUM> with wax coating <NUM>. Heating chamber <NUM> may heat wax coating <NUM> after its application onto streamer <NUM>, for example, to soften wax coating <NUM> so that wax coating <NUM> can be more evenly distributed on streamer <NUM>. Heating chamber <NUM> may use any suitable technique for heating, including heated air.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM>. Wax reservoir <NUM> may contain wax <NUM> in a solid state. In some embodiments, wax reservoir <NUM> may enclose streamer <NUM> as streamer <NUM> passes through wax reservoir <NUM>. Streamer <NUM> may pass through wax applicator <NUM> in the direction indicated by arrow <NUM> so that wax <NUM> may be transferred from wax reservoir <NUM> to streamer <NUM> as streamer <NUM> passes through wax reservoir <NUM>. With additional reference to <FIG>, wax reservoir <NUM> may include at least one opening <NUM> through which wax <NUM> may be forced onto streamer <NUM>. At least one opening <NUM> may face streamer passage <NUM> through which streamer <NUM> passes. As illustrated, wax application system <NUM> may include a supplemental chamber <NUM>. Supplemental chamber <NUM> may completely, or at least partially, enclose wax reservoir <NUM>. Supplemental chamber <NUM> may be connected to wax reservoir <NUM> so that pressure may be applied to wax reservoir <NUM> from supplemental chamber <NUM>. Any suitable mechanism may be used to apply force onto wax <NUM> in wax reservoir <NUM> from supplemental chamber <NUM>, including, but not limited to, air pressure or mechanical force (e.g., a mechanical spring). In some embodiments, wax <NUM> in wax reservoir <NUM> may be heated, for example, to make it more viscous (e.g., a semi-solid) to enable application onto streamer <NUM>. In some embodiments, a post-application heating treatment may be applied to wax coating <NUM>. For example, a heating chamber <NUM> (e.g., shown on <FIG>, <FIG>) may be used to heat wax coating <NUM> on streamer <NUM>.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax applicators <NUM>. As illustrated, wax applicators <NUM> may include wheel applicators <NUM>, wherein the wheel applicators <NUM> may include wax <NUM>. Two or more wheel applicators <NUM> may be positioned around the circumference of streamer <NUM>. In some embodiments, wax <NUM> may be in a liquid, semi-solid, or solid state. In some embodiments, wheel applicators <NUM> may be made substantially or entirely from wax <NUM> in a solid state in the general shape of a wheel. It should be understood that the general shape of a wheel is intended to include a cylindrical body. In some embodiments, wax <NUM> may be enclosed in a housing <NUM>. Housing <NUM> may include perforations <NUM> through which wax <NUM> may be squeezed for application onto streamer <NUM>. Pressure may be applied to wax <NUM> in housing <NUM> to squeeze wax through perforations <NUM>. Any suitable technique may be used for application of pressure, including, but not limited to air pressure or mechanical force (e.g., mechanical spring). In some embodiments, wax <NUM> in housing <NUM> may be in a liquid or semi-solid state. As illustrated, streamer <NUM> may pass through wheel applicators <NUM> in the direction indicated by arrow <NUM>. Wheel applicators <NUM> may engage streamer <NUM> so that wax <NUM> may be transferred from wheel applicators <NUM> to streamer <NUM>, forming wax coating <NUM>, as streamer <NUM> passes through wheel applicators <NUM>. In some embodiments, wheel applicators <NUM> may rotate in a direction (indicated by arrows <NUM>) that is opposite the direction indicated by arrow <NUM> of streamer <NUM> movement. In some embodiments, wheel applicators <NUM> may rotate such that there is a relative velocity between streamer <NUM> and wheel applicators <NUM>. In some embodiments, contact between wheel applicators <NUM> and streamer <NUM> may generate frictional energy. In some embodiments, the frictional energy may be sufficient to heat and soften wax <NUM>. In some embodiments, portions of wax <NUM> in proximity to wheel applicators <NUM> may soften prior to application onto streamer <NUM> so that wax <NUM> may be transferred to streamer <NUM>. In some embodiments, a post-application heating treatment may be applied to wax coating <NUM>. For example, a heating chamber <NUM> (e.g., shown on <FIG>, <FIG>) may be used to heat wax coating <NUM> on streamer <NUM>.

<FIG> illustrates another embodiment of wax application system <NUM> for application of wax <NUM> onto streamer <NUM>. As illustrated, wax application system <NUM> may include wax reservoir <NUM> and wax applicator <NUM>. Wax reservoir <NUM> may contain wax <NUM>, which may be in a solid or semi-solid state. In some embodiments, there may be more than one wax reservoir <NUM>, as shown on <FIG>. Wax applicator <NUM> may include brush applicators <NUM>. Brush applicators <NUM> may be operable to rotate about rotational axis <NUM>. Two or more brush applicators <NUM> may be positioned around the circumference of streamer <NUM>. Brush applicators <NUM> may contact streamer <NUM> as streamer <NUM> passes through brush applicators <NUM> in the direction indicated by arrow <NUM>. Brush applicators <NUM> may also contact wax <NUM> in wax reservoir <NUM> as brush applicators <NUM> rotate. Accordingly, as brush applicators <NUM> rotate, wax <NUM> from wax reservoir <NUM> may be transferred to brush applicators <NUM> and then deposited onto streamer <NUM>, forming wax coating <NUM>. In some embodiments, the brush applicators <NUM> may rotate in a direction (indicated by arrows <NUM>) that is opposite the direction indicated by arrow <NUM> of streamer <NUM> movement. In some embodiments, brush applicators <NUM> may rotate such that there is a relative velocity between streamer <NUM> and wheel applicators <NUM>. In some embodiments, a post-application heating treatment may be applied to wax coating <NUM>. For example, a heating chamber <NUM> (e.g., shown on <FIG>, <FIG>) may be used to heat wax coating <NUM> on streamer <NUM>.

Claim 1:
A marine geophysical survey system, comprising:
a streamer (<NUM>) disposed along a spooling block (<NUM>); and
a wax application system (<NUM>) operable to clean the streamer (<NUM>) and apply a wax coating to the streamer as the streamer is being deployed from the survey vessel (<NUM>) into a body of water (<NUM>), the wax application system (<NUM>) comprising:
a wax applicator (<NUM>); and
a cleaning unit (<NUM>) comprising a fluid application unit (<NUM>), a drying unit (<NUM>) operable to apply air onto the streamer (<NUM>) and an air drier operable to remove moisture from the air prior to directing the air onto the streamer (<NUM>),
wherein the wax applicator (<NUM>) is configured to independently control an amount of wax applied to the streamer (<NUM>) such that a thickness of the wax coating is independent of a speed the streamer (<NUM>) passes through the wax applicator (<NUM>).