Fugro N.v.

Fugro Technology B.v.

Fnv IP B.v.

Angus James Stephen Ogilvie

Andrew Paul Cowlard

A marine survey system and method for ultrahigh resolution (UHR) mapping of a marine bottom (B) below a body of water (W) by means of a frame () towed as a whole by one or more towing cables () at a distance (Xf) behind a marine vessel () moving over the water (W) in a movement direction (V). The frame () comprises a rigid framework () and a plurality of independent acoustic sources (), wherein each acoustic source () is independently controlled to emit a separate acoustic wave (A) propagating through the water (W) and reflecting off bottom regions of the marine bottom (B) for the mapping thereof. The acoustic sources () are kept fixated by the rigid framework () at a source-to-source distance (Ys) less than four meters in a transverse direction (Y) perpendicular to the movement direction (V) of the vessel () to distinguish the bottom regions with an ultrahigh resolution (Ry) of less than two meters at least in the transverse direction (Y).

Frame with acoustic sources for marine survey

Disclosed is a pressure tolerant seismic source for deep water survey. The seismic source can include an electromagnetic coil for generating an electromagnetic pulse, a piston plate movable by said electromagnetic pulse, and a housing with a first chamber and a second chamber separated by each other via a common bulkhead arrangement. The seismic source can also include that the coil is arranged within the first chamber and the piston plate arranged within the second chamber. The seismic source can also include the second chamber is at least partly filled with a liquid coupled to the plate so that due to movement of the plate at least one pressure pulse is generated traveling through the liquid within said second chamber.

Pressure tolerant seismic source

A system for surveying the structure beneath the seabed, comprising: a survey vessel; a streamer comprising a cable, a first set of Nsensor groups positioned at a first end portion of the cable, the sensor groups of the first set being spaced from each other by a group interval, and a second set of Nsensor groups positioned at a second end portion of the cable, the sensor groups of the second set being spaced from each other by the group interval; a sound source; wherein, when the system is in use, the survey vessel travels at a predetermined speed, towing the streamer and the sound source such that the sound source is positioned adjacent an intermediate portion of the cable between the first and second end portions of the cable; the sound source sends acoustic pulses at a predetermined period between pulses towards the seabed such that reflections are produced towards both the first set of sensor groups and the second set of sensor groups; and the speed of the survey vessel and the predetermined period of the sound source are selected such that the shot point interval of the sound source equals the group interval.

Marine surveying

Disclosed is a system for surveying the structure beneath the seabed using a sub-bottom profiler. The system can include a survey vessel and a sub-bottom profiler mounted to travel with the survey vessel. The sub-bottom profiler can comprise a transmitter for transmitting pulses at a predetermined period between pulses towards the seabed, and a first receiver and a second receiver for receiving reflections from the seabed of each transmitted pulse. The system can also include that the transmitter and the first and second receivers are mounted along an axis in the direction of travel of the survey vessel and the transmitter is disposed between the first and second receivers and spaced from each of them by a predetermined separation.

Disclosed is a system for acoustically exploring structure of a floor below a water body. The system can comprise a vessel, at least one streamer placed in the water and towed by the vessel. The system can also comprise a plurality of acoustic sensors positioned at regular intervals along the length of the streamer. The longitudinal direction of the streamer can make an angle with the horizontal. The system can also comprise a source for generating acoustic pulses placed in the water and towed by the vessel using a tow line. The tow line can have such length that the horizontal distance between the vessel and the source is larger than the horizontal distance between the vessel and the first sensor closest to the vessel and smaller than the horizontal distance between the vessel and the last sensor most remote from the vessel.

Growing community of inventors

Aberdeen, United Kingdom

Angus James Stephen Ogilvie