Abstract: Systems and methods for marine seismic surveying of strata beneath a seafloor are disclosed, including, in certain aspects, locating an under water sensor cable with sensing apparatus on a seafloor beneath water; the cable having a first end connected to a first unmanned powered vehicle and a second end connected to a second unmanned powered vehicle; and, with the two vehicles, locating, moving, re-locating, raising, and/or maintaining tension on the cable. This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).

Abstract: An electromagnetic survey sensing device includes at least two electrodes disposed at spaced apart locations. An electrical to optical converter is electrically coupled to the at least two electrodes. The converter is configured to change a property of light from a source in response to voltage imparted across the at least two electrodes. The device includes an optical fiber optically coupled to an output of the electrical to optical converter, the optical fiber in optical communication with a detector.

Abstract: A marine seismic streamer steering device comprises a body connected between two adjacent sections of the seismic streamer, at least one inlet port on the body, a plurality of outlet ports on the body, and a port control unit which controls water flow through the plurality of water outlet ports. The steering device further comprises a roll sensor which determines rotational orientation of the body and transmits the orientation to the port control unit, a lateral position sensor which determines lateral position of the body and transmits the lateral position to the port control unit, and a depth sensor which determines depth of the body and transmits the depth to the port control unit. The port control sensor then controls the water flow through the plurality of outlet ports based on the transmitted rotational orientation, lateral position, and depth of the body.