Patent application number | Description | Published |
20110317514 | Method and system for streamer depth control - Depth and tilt control systems for geophysical sensor streamers and methods of use are discussed. Such systems may include a plurality of tilt sensors disposed at spaced apart locations along the geophysical sensor streamer, each tilt sensor having a first tilt sensing element arranged to measure tilt of the geophysical sensor streamer proximate the associated spaced apart location, a plurality of LFD control devices, each disposed proximate one of the tilt sensors along the geophysical sensor streamer, and a plurality of microcontrollers, each microcontroller in signal communication with at least one of the LFD control devices and its associated tilt sensor, wherein each microcontroller is capable of utilizing the tilt measured by the associated tilt sensor to selectively operate the associated LFD control device to cause the geophysical sensor streamer to align with a selected depth profile. | 12-29-2011 |
20120113746 | Noise Suppression by Adaptive Speed Regulations of Towed Marine Geophysical Streamer - A method for towing marine geophysical sensor streamers in a body of water includes moving a towing vessel at a selected speed along the surface of the body of water. At least one geophysical sensor streamer is towed by the vessel at a selected depth in the water. A velocity of the streamer in the water is measured at at least one position along the streamer. The selected speed of the towing vessel is adjusted if the measured velocity is outside of a selected range. | 05-10-2012 |
20120182017 | Subsurface electromagnetic survey technique using expendable conductivity, temperature, and depth measurement devices - A method for modeling conductivity distribution in a formation below a body of water includes measuring electromagnetic response of the formation with an electromagnetic survey system; measuring at least one of water conductivity, water dielectric constant, and water temperature with respect to depth in the water; generating an initial model of conductivity distribution of the formation; discretizing the measurements of at least one of water conductivity, water dielectric constant, and water temperature with respect to depth into at least one layer; generating a forward model of a response of the electromagnetic survey system to the initial model and the discretized measurements; comparing the forward model to the measured electromagnetic response to determine differences; adjusting the initial model to reduce the differences; and repeating generating a forward model, comparing the forward model to the measured electromagnetic response, and adjusting the initial model until the differences fall below a selected threshold. | 07-19-2012 |
20120230150 | Method for determining positions of sensor streamers during geophysical surveying - The geodetic position of a point on a streamer towed by a vessel in a body of water may be determined. Geodetic positions of a plurality positions along at least two of a plurality streamers towed in the body of water may be determined. Positions may be selected from the plurality of positions. Distances between pairs of the selected positions and between each of the selected positions and the point may be determined. Geodetic position of the point may be determined using the geodetic positions and distances. | 09-13-2012 |
20120236684 | SENSOR ARRANGEMENT FOR DETECTING MOTION INDUCED NOISE IN TOWED MARINE ELECTROMAGNETIC SENSOR STREAMERS - An electromagnetic sensor streamer may include a jacket, at least one electromagnetic sensor in operational communication with a voltage measuring circuit disposed inside the jacket, and at least one wire coil. The at least one wire coil is in signal communication with the voltage measuring circuit, and the voltage measuring circuit is configured to determine motion-induced voltages imparted to the at least one electromagnetic sensor in the streamer. | 09-20-2012 |
20130114374 | ADJUSTABLE SENSOR STREAMER STRETCH SECTION FOR NOISE CONTROL FOR GEOPHYSICAL SENSOR STREAMERS - A sensor streamer stretch section includes at least one spring. A means for coupling the spring at each end to at least one of a sensor streamer and a lead in cable is included. A cable is coupled at its ends to the means for coupling. The cable is capable of carrying at least one of electrical and optical signals. The cable is formed such that the cable undergoes substantially no axial strain when the shock cord is elongated. An adjustable damper is coupled between the means for coupling at each end of the stretch section. | 05-09-2013 |
20130155807 | METHOD FOR DETERMINING POSITIONS OF SENSOR STREAMERS DURING GEOPHYSICAL SURVEYING - A method for determining geodetic position of at least one point on a geophysical sensor streamer towed by a vessel in a body of water includes determining geodetic positions of a plurality of locations along a first geophysical sensor streamer towed at a first depth in the body of water. A lateral offset is caused between the first geophysical sensor streamer and a second geophysical sensor streamer towed at a second depth in the body of water. A distance is measured between at least two selected points along the first geophysical sensor streamer and a selected point along the second geophysical sensor streamer. A depth is measured at at least one point along the second geophysical sensor streamer. A geodetic position is determined at a selected point along the second geophysical sensor using the depth measurement, a direction of the lateral offset and the measured distances. | 06-20-2013 |
20130300420 | Acquisition System and Method for Towed Electromagnetic Sensor Cable and Source - An electromagnetic survey acquisition system includes a sensor cable and a source cable, each deployable in a body of water, and a recording system. The sensor cable includes an electromagnetic sensor thereon. The source cable includes an electromagnetic antenna thereon. The recording system includes a source current generator, a current sensor, and an acquisition controller. The source current generator powers the source cable to emit an electromagnetic field from the antenna. The current sensor is coupled to the source current generator. The acquisition controller interrogates the electromagnetic sensor and the current sensor at selected times in a synchronized fashion. | 11-14-2013 |
Patent application number | Description | Published |
20130010570 | Towing Methods and Systems for Geophysical Surveys - Disclosed are methods and systems for controlling spread and/or depth in a geophysical survey. An embodiment discloses a method for geophysical surveying, comprising: towing two streamers laterally spaced apart through a body of water at a depth of at least about 25 meters, each of the streamers comprising geophysical sensors disposed thereon at spaced apart locations; maintaining lateral separation of at least about 150 meters between the two streamers using at least two submersible deflectors, the two submersible deflectors being individually coupled to one of the two streamers; and detecting signals using the two geophysical sensors while the two streamers are towed at the depth of at least about 25 meters. | 01-10-2013 |
20130010571 | Towing Methods and Systems for Geophysical Surveys - Disclosed are methods and systems for controlling spread and/or depth in a geophysical survey. An embodiment discloses a submersible deflector, comprising: an upper portion comprising an upper fin section and upper foils disposed below the upper fin section, wherein at least one slot is defined between the upper foils; and a lower portion coupled to the upper portion and disposed below the upper portion, wherein the lower portion comprises a lower fin section and lower foils disposed above the lower fin section, wherein at least one slot is defined between the lower foils. Also disclosed are marine geophysical survey systems and methods of performing geophysical surveys. | 01-10-2013 |
20130025362 | Methods and Systems for Streamer Depth Profile Control - Disclosed are methods and systems for controlling depth profiles of marine geophysical sensor streamers as they are towed in a body of water. An embodiment discloses a method for marine geophysical surveying, the method comprising: towing a geophysical sensor streamer in a body of water having a surface and a floor, the geophysical sensor streamer being coupled to a survey vessel by a lead-in cable, the lead-in cable having a length that extends from the survey vessel; adjusting the length of the lead-in cable to cause a forward end of the geophysical sensor streamer to follow a depth profile; and deflecting the geophysical sensor streamer in the vertical plane at one or more spaced apart locations. | 01-31-2013 |
20130148468 | NOISE REDUCTION SYSTEMS AND METHODS FOR A GEOPHYSICAL SURVEY CABLE - A disclosed geophysical survey cable includes a signal amplifier coupled between two electrodes spaced apart along the length of the geophysical survey cable (the electrodes being coupled to the signal amplifier by a first conductor pair), and a noise amplifier coupled to a second conductor pair positioned substantially parallel to the first conductor pair. The geophysical survey cable further includes a combiner that combines a noise signal provided by the noise amplifier with a sensor signal provided by the signal amplifier to provide a sensor signal with a reduced noise component. | 06-13-2013 |
20130162255 | ELECTROMAGNETIC GEOPHYSICAL SURVEY SYSTEMS AND METHODS EMPLOYING ELECTRIC POTENTIAL MAPPING - The present disclosure describes various geophysical survey systems and methods for mapping an electric potential field. At least one illustrative embodiment includes an electromagnetic (EM) source and geophysical survey cables that each includes multiple electrodes spaced apart along each geophysical survey cable's length, and multiple data acquisition units that each obtains measurements indicative of an electric potential between two the electrodes. A calculation module is included and configured to combine signals representative of the measurements to produce signals indicative of the electric potential of each electrode relative to a reference potential assumed to be present at a selected electrode for each of the plurality of geophysical survey cables. Each reference potential is assumed to be of a magnitude that is within a tolerance range of a common reference potential. | 06-27-2013 |
20130166210 | Electromagnetic Geophysical Survey Systems and Methods Employing Electric Potential Mapping - The present disclosure describes various geophysical survey systems and methods for mapping an electric potential field. At least one illustrative embodiment includes an electromagnetic (EM) source and geophysical survey cables that each includes multiple electrodes spaced apart along each geophysical survey cable's length, and multiple data acquisition units that each obtains measurements indicative of an electric potential between two the electrodes. A modeling module is included and configured to calculate a reference potential at a selected electrode for each of the plurality of geophysical survey cables, as well as a calculation module to combine signals representative of the measurements to produce signals indicative of the electric potential of each electrode relative to the reference potential. | 06-27-2013 |
20130221969 | METHODS AND APPARATUS FOR ADAPTIVE SOURCE ELECTROMAGNETIC SURVEYING - Disclosed are methods and apparatus for adaptive source electromagnetic (EM) surveying. In accordance with one embodiment, a source waveform signal is generated, and an outgoing EM signal which is based on the source waveform signal is transmitted using an antenna. A responsive electromagnetic signal is detected using at least one electromagnetic sensor, and a receiver waveform signal based on the responsive electromagnetic signal is obtained. A feedback control signal which depends on at least one input signal is determined. Based on the feedback control signal, the source waveform signal is adapted. Other embodiments, aspects, and features are also disclosed. | 08-29-2013 |