Methods and apparatus are described for reducing noise in measurements made by one or more pressure sensors disposed in a cable having a generally longitudinal axis. Estimated axial vibration noise at a location along the cable is determined based at least in part on measurements from one or more motion sensors disposed along the cable. The estimated axial vibration noise is subtracted from pressure sensor measurements corresponding to the location. The result is noise-attenuated pressure sensor measurements corresponding to the location.

Method and apparatus for suppressing cable dynamics in a device towed in water. The apparatus includes at least one section for suppression of motion, wherein the at least one section includes an axial motion suppression section; and the axial motion suppression section comprising equipment for the attenuation of axial vibrations in an electro-mechanical cable. The equipment is configured to produce a digressive stiffness curve.

A seismic apparatus includes one or more seismic cable systems configured to acquire seismic data, each seismic cable system having one or more of a cable jacket, a reservoir for a ballast fluid or other ballast medium, and an actuator or other transfer mechanism configured to transfer the ballast fluid between the reservoir and the seismic cable system during acquisition of the seismic data, e.g., where the ballast fluid is transferred to the seismic cable system within the cable jacket. A controller can be configured to adjust a buoyancy of the seismic cable system responsive to the transfer of the ballast fluid, e.g., where the internal volume expands or contract based on the fluid transfer.

Disclosed are methods and systems that include a multiple-tube electrode assembly. An embodiment discloses an electrode assembly, comprising: a carrier body comprising an elongated support; and electrically conducting surfaces longitudinally spaced along the carrier body, wherein the electrically conducting surfaces are electrically coupled in parallel.

An apparatus for collecting geophysical information may include a geophysical information station disposed along a seismic communication cable. A bypass circuit responsive to a command signal is in communication with a switching circuit that is operable to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal. An exemplary method for bypassing a geophysical information station in a geophysical information collection system includes sending a command signal to a bypass circuit and activating one or more switching circuits using the bypass circuit to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal.

Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

Systems and methods are provided for operating streamer recovery devices to retrieve seismic streamers, for example streamers that become severed from their towing vessels. The streamer recovery can be remotely activated to cause the streamer to surface where the streamer is more easily retrieved.

It is proposed a method for monitoring an electrical power supply line comprised in a seismic cable and extending along the seismic cable. The seismic cable includes: a plurality of seismic sensors arranged along the seismic cable, a plurality of controllers arranged along the seismic cable, and an optical transmission line extending along the seismic cable for carrying data signals from or towards the controllers. The electrical power supply line supplies at least one pair of master and slave controllers. The master controller of a given pair of master and slave controllers performs a step of monitoring a portion of the electrical power supply line between the master and slave controllers, by using an optical loop established on a portion of the optical transmission line between the master and slave controllers, and starting from the master controller and passing through the slave controller.

Disclosed herein are various embodiments of a method and apparatus to enhance spatial sampling in all nominally horizontal directions for Dual-Sensor seismic data at the bottom of a body of water such as the ocean. The sensor apparatus on the water bottom is comprised of sensing elements for linear particle motion, for rotational motion, for pressure measurement, for pressure gradients, and for static orientation. Stress and wavefield conditions known at the water bottom allow numerical calculations that yield enhanced spatial sampling of pressure and nominally vertical linear particle motion, up to double the conventional (based on physical sensor locations) Nyquist spatial frequency in two nominally horizontal independent directions. The method and apparatus have a wide range of application in Ocean Bottom Seismic 3D, 4D, and Permanent Reservoir Monitoring surveys, and other marine seismic surveys, in oil and gas exploration and production.

A cable that include a hose having a conductor located thereabout. A first strength member layer is located about the conductor. A second strength member layer is located about the first strength member layer. A first jacket is located about the second strength member layer. The first jacket is fiber-reinforced. A second jacket is located about the first jacket. The second jacket is a contrasting color to the first jacket.