Abstract:
Methods, systems, and apparatuses are disclosed for sensing acoustic waves in a medium. One example system includes a first elongated member, a first motion sensor sensitive to vibrations of the first elongated member, a second motion sensor spaced apart from the first motion sensor and also sensitive to vibrations of the first elongated member, and a first vibration source operably coupled to the first elongated member and configured to vibrate the first elongated member.
Abstract:
Presented are methods and systems for collecting marine seismic data. The collected seismic data can be low frequency (e.g., less than 10 Hz) or it can be a full seismic bandwidth (1-200 Hz) depending on if the low frequency tuned sources and tuned receivers are combined with conventional sources and receivers. The low frequency sources can be towed or they can be autonomous and positioned in the survey area by tether, drifting or self-propelled. The tuned low frequency receivers are towed at a depth greater than conventional receivers and the sources can be fired independently or simultaneously.
Abstract:
A geophysical sensor cable has one or more sensor cable sections. Each of the sensor cable sections is provided with seismic and electromagnetic sensors arranged along said cable. The seismic sensors include a hydrophone and a seismic component receiver for seismic vector measurements while the sensor cable is at the sea-floor. The electromagnetic sensors include both E-field sensors and H-field sensors. The E-field sensors include pairs of first and second electrodes arranged with different positions along the cable and connected to a voltage amplifier. The H-field sensors include three mutually orthogonally arranged H-field component sensors.
Abstract:
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.
Abstract:
Retriever systems for marine geophysical survey sensor streamers. At least some of the illustrative embodiments are methods including attaching a retriever system to a sensor streamer by: wrapping a lifting bag assembly at least partially around the sensor streamer, the lifting bag assembly comprising a deflated lifting bag, a gas cylinder, and a depth trigger mechanism; and covering the lifting bag assembly with an outer cover.
Abstract:
A seismic streamer includes a jacket covering an exterior of the streamer. At least one strength member extends the length of the jacket. The strength member is formed as a substantially flat belt having a width to thickness ratio of at least 10. At least one sensor holder is coupled to the at least one strength member. The at least one sensor holder includes at least one arcuate opening for receiving the at least one strength member. The at least one arcuate opening is laterally displaced from a center of the at least one sensor holder such that when the at least one strength member is disposed therein the at least one strength member is substantially tube shaped and substantially coaxial with the jacket.
Abstract:
This disclosure is related to the field of streamers. In one embodiment, a streamer may include a group of particle motion sensors. In some embodiments, at least two of the particle motion sensors in the group are movable relative to one another within the streamer, and the two particle motion sensors are configured to measure motion along a particular axis. In some embodiments, the streamer may additionally include a plurality of pressure sensors.
Abstract:
Sensor stations, system and methods for sensing seismic parameters of a subsurface structure are provided. The sensor station includes a sensor housing and a sensor unit. The sensor housing includes a base with a removable lid and receptacles for receiving the fiber optic cable therethrough. The base has a cavity therein accessible upon removal of the removable lid. The sensor unit is positionable in the cavity of the sensor housing. The sensor unit is operatively connectable to a portion of the optical fibers of the fiber optic cable for communicating seismic data sensed by the sensor unit.
Abstract:
Disclosed herein is a system of acquiring seismic date in a marine environment, which includes: seismic streamers towed by a vessel; and means for detecting and/or locating marine mammals, characterised in that said marine mammal detection and/or location means are secured to said seismic streamers.