Pgs Geophysical as

Pgs Norway Geophysical as

Jan Erik Stokkeland

Rune Tønnessen

Mattias Dan Christian Oscarsson

Martin Austad

Ole-Fredrik Semb

Karl Petter Elvestad

Anders Goran Mattsson

Jon Falkenberg

Disclosed are methods and systems for using tension feedback from steerable deflectors. In one example, a method may comprise: towing sensors streamers in a body of water from a survey vessel, wherein each of the sensor streamers comprises geophysical sensors at spaced apart locations; towing steerable deflectors in the body of water from the survey vessel, wherein the steerable deflectors are used to provide a lateral component of force to the sensors streamers as the steerable deflectors are towed through the body of water; turning the survey vessel; measuring tension at the steerable deflectors during the step of turning the survey vessel; and in response to the step of measuring tension, determining at least one of a reduced vessel operating speed, an increased vessel operating speed, a reduced angle of attack for at least one of the steerable deflectors, an increased angle of attack for at least one of the steerable, an increased vessel turn radius, or a decreased vessel turn radius.

Method and system for adjusting vessel turn time with tension feedback

Disclosed are methods and systems for using tension feedback from steerable deflectors to adjust vessel turn time. In one example, a maximum tension for a second steerable first towed on a first side of the survey vessel may be determined. A radius of a turn of the vessel at a preselected speed may further be selected such that the tension on the first steerable deflector is less than the maximum tension. The vessel may be turned while moving at the preselected speed, wherein the turning of the vessel has the selected radius. Tension may be measured on the first steerable deflector during the step of turning the vessel.

A paravane for a seismic acquisition system includes a float, a frame suspended from the float, deflectors affixed to the frame, and means for coupling a tow rope to a lead-in functionally extending between a forward end and an aft end of the frame. The paravane includes means for selectively changing an effective position along the lead-in of the means for coupling the tow cable.

Steerable paravane system for towed seismic streamer arrays

Controlling lateral force developed by a paravane system. At least some of the illustrative embodiments are methods including: towing a paravane system through water, the towing by way of a bridle comprising a plurality of fixed-length forward lines coupled to a respective plurality of forward tow points, and a plurality of fixed-length aft lines coupled to a respective plurality of aft tow points; and while towing the paravane system through the water changing one or both of the lateral force supplied by the paravane or the direction of the force supplied by the paravane.

System and method of controlling force developed by a paravane system

A method for towing a sensor streamer array in a body of water includes towing a plurality of sensor streamers behind a vessel in the water, measuring tension at a plurality of positions along the array and determining at least one of an optimum operating speed for the vessel, when the streamers and associated towing equipment have become affected by marine debris so as to require cleaning, and an optimum angle of attack of at least one paravane in the towing equipment.

Tension management control system and methods used with towed marine sensor arrays

A lateral force and depth control device for a marine streamer includes a housing configured to be coupled within the streamer. A control surface is mounted to the housing such that a rotary orientation and an angle of attack of the control surface with respect to the housing are changeable. The device includes means for moving the control surface to a selected rotary orientation with respect to the housing. The device includes means for moving the control surface to a selected angle of attack with respect to the housing. A removable coupling is provided to couple the control surface to the means for moving to a selected rotary orientation and means for moving to a selected angle of attack.

Single foil lateral force and depth control device for marine seismic sensor array

A paravane for a marine seismic survey system includes a float and at least one diverter operatively coupled to the float. The diverter is configured to redirect flow of water past the paravane with respect to a direction of motion of the paravane through water. The paravane also includes a steering device. The steering device is configured to controllably redirect the flow of water so as to control an amount of lateral force generated by the paravane.

Growing community of inventors

Heggedal, Norway

Jan Erik Stokkeland