Patent application number | Description | Published |
20110182138 | Method and system for streamer depth control - A depth and level control system for a geophysical streamer according to one aspect of the invention includes a plurality of tilt sensors disposed at spaced apart locations along the streamer. The tilt sensors each have a first tilt sensing element arranged to measure tilt of the streamer along a longitudinal dimension thereof. A controller is in signal communication with each tilt sensor. A depth control device is in signal communication with each controller. The controller is programmed to operate the depth control device to cause the streamer to be level as measured by the tilt sensor. | 07-28-2011 |
20110205839 | Method for towing marine sensor streamers - A method for operating a geophysical sensor streamer in body of water includes operating a remotely operated vehicle coupled to a forward end of the streamer to tow the streamer in the water. Signals generate by sensors on the streamer are communicated substantially in real time to a recording unit on a survey vessel using at least one of electrical and optical cables in an umbilical cable connecting the remotely operable vehicle to the survey vessel. | 08-25-2011 |
20110210741 | Structure for magnetic field sensor for marine geophysical sensor streamer - A marine electromagnetic sensor cable includes a first jacket covering an exterior of the cable. At least one wire loop is disposed on the exterior of the first jacket. The wire loop is shaped to have a magnetic dipole moment along a selected direction. A contact ring is disposed inside the first jacket to make electrical connection between the at least one wire loop and an associated signal processing circuit disposed inside the first jacket. | 09-01-2011 |
20110242940 | Noise suppression by adaptive speed regulation 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 exceeds a selected threshold. | 10-06-2011 |
20110248718 | Marine sensor streamer having pressure activated stiffness enhancement - A marine sensor streamer includes a jacket covering an exterior of the streamer. At least one strength member extends the length of the jacket. At least one stiffener element extends inside the length of the jacket. The at least one stiffener element includes a gas filling the interior of a flexible, compressible tube and filler elements disposed in the gas. The filler elements have exterior shape and surface roughness such that upon compression of the gas, the filler elements are urged into contact with each other, causing the streamer to become substantially rigid. | 10-13-2011 |
20110255368 | Method for 2D and 3D electromagnetic field measurements using a towed marine electromagnetic survey system - A method for acquiring electromagnetic data in at least two dimensions includes towing a first streamer cable behind a vessel in a body of water, the first streamer cable including a reference line extending substantially along the entire length thereof, a plurality of spaced apart measuring electrodes electrically insulated from the reference line and a voltage measuring circuit functionally coupled between each measuring electrode and the reference line. At least a second streamer cable is towed at corresponding distance from the vessel. The second streamer cable is configured substantially as the first streamer cable. The second streamer cable is displaced from the first streamer cable in one of a horizontal plane and a vertical plane. At selected times an electromagnetic field is imparted into the water. Voltage difference is determined between each measuring electrode and the reference line, and a difference between voltages measured at least one electrode on each of the first and second streamer cables is determined. | 10-20-2011 |
20110260730 | Switchable front-end measurement unit for towed marine electromagnetic survey cables - A marine electromagnetic streamer includes a plurality of electrodes disposed along a longitudinal dimension of the streamer. At least one signal processing module is disposed at a selected position along the streamer. A multipole switch associated with the at least one module is electrically coupled between a signal input of the signal processing module and selected pairs of the electrodes. The switch is configured to enable the selected pairs coupled to the switch such that selection thereof results in at least one of selected electrode spacing and selected electrode offset from an electromagnetic energy source. | 10-27-2011 |
20110273179 | Multiple component electromagnetic survey signal acquisition method - A method for marine electromagnetic surveying includes transmitting a first electromagnetic field oriented in a first direction into a body of water. A second electromagnetic field oriented in a second direction is transmitted into the body of water, wherein the second direction is substantially transverse to the first direction. A parameter related to electromagnetic field amplitude is detected at a plurality of longitudinally and laterally spaced apart positions behind a vessel. The components of the detected electromagnetic field parameter are resolved into components along the first and second directions by using the geometrical symmetries and asymmetries of the transmitting source. Systems for implementing such methods are also provided. | 11-10-2011 |
20110279120 | Electromagnetic survey systems and methods with rotation-corrected motion compensation - A disclosed electromagnetic survey system includes one or more streamer(s) having multiple electromagnetic sensors and motion sensing units. Each motion sensing unit has one or more accelerometer(s) to measure motion perpendicular to an axis of the streamer, and a rotation sensor to measure rotation about the axis. The measurements of the accelerometer are adjusted based on measurements from the rotation sensor. The survey system also includes one or more processor(s) that determine, for each electromagnetic sensor, a motion signal based on the adjusted measurements. A described electromagnetic survey method includes processing acceleration and rotational motion measurements to obtain an orientation of motion sensing units as a function of time. The measured acceleration is manipulated based on the orientation to obtain one or more velocity signal(s) for each motion sensing unit. Interpolation is performed on the velocity signals to determine at least one velocity signal for each electromagnetic sensor. | 11-17-2011 |
20110291658 | High resolution three dimensional electromagnetic survey method - A method for electromagnetic surveying below the bottom of a body of water includes deploying a plurality of nodal recording devices in a selected pattern on the water bottom. An electromagnetic transmitter is towed in the water. At least one electromagnetic sensor streamer is concurrently towed in the water. The electromagnetic transmitter is actuated at selected times and signals detected by sensors in the nodal recording devices and in the at least one streamer are recorded. | 12-01-2011 |
20110292759 | Structure for marine electromagnetic sensor streamer suited for manufacturing by extrusion - A method for making a marine electromagnetic survey streamer includes affixing connectors to longitudinal ends of a strength member. At least one signal communication line is extended along the length of the strength member. The strength member, connectors, and at least one signal communication line form a mechanical harness. Electrodes are affixed to the mechanical harness at selected positions. The mechanical harness is drawn through a co-extruder. The co-extruder fills void spaces in the harness with a void fill material. The co-extruder applies a jacket to an exterior of the void filled harness. | 12-01-2011 |