A marine streamer includes: an optical fiber disposed along a length of the streamer; a light source; and light analysis equipment, wherein: the length is at least 20 km, a diameter of the streamer is no more than 25 mm, the optical fiber, light source, and light analysis equipment are configured to provide a receiver sampling density of at least 1 per meter, and the streamer is configured to be towed nominally horizontally through a body of water. A method of marine surveying includes: towing a streamer spread at a first depth of 10 m to 30 m with a survey vessel; and towing Distributed Acoustic Sensing (DAS) streamers at a second depth of greater than 30 m. A method includes: acquiring long-offset data with sensors distributed along the DAS streamers.

Systems and methods for removing galvanic distortion caused by near-surface inhomogeneities from surface-to-borehole (STB) measurements are disclosed. Corrected STB measurements may provide for a representation of the resistivity of an oil-bearing reservoir and may be used to determine movement of a waterfront within the reservoir caused by waterflooding of the reservoir.

Techniques are disclosed relating to geophysical surveying. In some embodiments, a marine survey vessel tows multiple sensor streamers in addition to vibratory sources deployed relative to the sensor streamers. In some embodiments, the vessel tows vibratory sources emitting energy within different frequency bands in different deployment zones. In some embodiments, one or more sources are driven with different sweep functions, different activation patterns, and/or different sweep lengths. Various disclosed techniques for manufacturing a geophysical data product may potentially simplify equipment used for towing sources, reduce survey complexity without reducing resolution, increase resolution without increasing survey complexity, improve energy content recovered from deep reflections, and/or reduce the environmental impact of emitting seismic energy.

A seismic survey system is provided. The system can include a source array including a first sub-source array and a second sub-source array. The system can include a streamer coupled with the first sub-source array and a streamer coupled with the second sub-source array. The system can include a receiver array including a plurality of receivers. The system can include a lateral cable coupled with at least one of a first diverter or a second diverter and at least one of the first sub-source array or the second sub-source array. The system can include a positioning cable coupled with the first diverter and a positioning cable coupled with the second diverter. The system can include a power cable. The system can include a seismic data acquisition unit array including a plurality of seismic data acquisition units disposed on a seabed.

The present disclosure is directed to systems and methods of facilitating a seismic survey and locating seismic data acquisition units in a marine environment. The system can include a first seismic data acquisition unit. The first seismic data can include a cleat ring to couple the first seismic data acquisition with a second seismic data acquisition unit. The system can include a rope having a first end coupled to a first portion of the first seismic data acquisition unit and a second end coupled to a second portion of the first seismic data acquisition unit. The system can include a cavity formed by the cleat ring. The system can include a telltale component coupled to a portion of the rope. The rope and the telltale component can be stored in the cavity of the first seismic data acquisition unit.

Numerous techniques and apparatus are disclosed relating to the performance of 4D marine geophysical surveys over at least first and second areas covered, respectively, by first and second preexisting baseline surveys. Performing the monitor surveys may include deploying a monitor survey streamer layout that can be used to repeat streamer positions of both the first and the second preexisting baseline surveys, and using the monitor survey streamer layout to perform the monitor survey over the first and second areas in a manner that repeats all streamer positions of the first preexisting baseline survey when over the first area, and that repeats all streamer positions of the second preexisting baseline survey when over the second area. Streamer layouts corresponding to the first and second preexisting baseline surveys may differ in at least one of the following characteristics: streamer separation or total number of streamers.

A seabed object detection system is provided. The system can include a receiver array. The receiver array can include a plurality of receivers disposed on a plurality of streamers. The plurality of streamers can include a central port side streamer, a central starboard side streamer, an auxiliary port side streamer and an auxiliary starboard side streamer. The system can include a source array. The source array can include a plurality of sources. The plurality of sources can include a central port side source, a central starboard side source, an auxiliary port side source, and an auxiliary port side streamer. The source array towed during a first pass can define a first path. The source array towed during a second pass can define a second path. The first path can be interleaved with the second path such that the first path overlaps the second path.

A seabed object detection system is provided. The system can include a receiver array including streamers. The system can include a plurality of receivers coupled with the streamers. The system can include a receiver array cross-cable to couple with the first streamer and to couple with the second streamer. The receiver array cross-cable can be disposed at a first depth of a body of water. The system can include a first diverter and a second diverter coupled with the receiver array cross-cable. The system can include a source array including a first source and a second source. The source array can be coplanar to the receiver array. The system can include a source array cross-cable to couple with the first source and to couple with the second source, the source array cross-cable disposed at a second depth of the body of water.

A seabed object detection system is provided. The system can include a receiver array including a first streamer and a second streamer. The system can include a first plurality of receivers coupled with the first streamer and a second plurality of receivers coupled with the second streamer. The system can include a receiver array cross-cable to couple with the first streamer and the second streamer. The system can include a source array including a first source and a second source. The system can include a first source cable coupled with the first source and a second source cable coupled with the second source. The system can include a source array cross-cable to couple with the first source cable and the second source cable. The system can include a first lateral cable to couple with a first diverter and second lateral cable to couple with a second diverter.

A seabed object detection system is provided. The system can include a receiver array including streamers. The system can include a plurality of receivers coupled with the streamers. The system can include a receiver array cross-cable to couple with the first streamer and to couple with the second streamer. The receiver array cross-cable can be disposed at a first depth of a body of water. The system can include a first diverter and a second diverter coupled with the receiver array cross-cable. The system can include a source array including a first source and a second source. The source array can be coplanar to the receiver array. The system can include a source array cross-cable to couple with the first source and to couple with the second source, the source array cross-cable disposed at a second depth of the body of water.