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 long offset land seismic survey spread includes a plurality of sensors within an area thereby defining a sensor receiver patch, a plurality of long offset sensor receivers outside of the receiver patch thereby surrounding the receiver patch and defining a sensor long offset area that is fee from sensor receivers that also defines a distance separating an external border of the sensor receiver patch and the long offset sensor receivers being a minimum offset distance that is a long offset distance.

A method and apparatus for data acquisition including: acquiring a first set of data for a survey area with streamer receivers on a streamer spread; and simultaneously acquiring a second set of data for the area with ocean bottom receivers, the first and second sets of data together forming a complete dataset for velocity modeling and imaging. A method including: navigating a first propulsion source along a first path in the area, wherein a streamer spread and a first seismic source are coupled to the first propulsion source; navigating a second propulsion source along a second path in the area, wherein a second seismic source is coupled to the second propulsion source; while navigating the first and second propulsion sources, activating at least one of the first and second seismic sources; and acquiring data with receivers on the streamer spread and with ocean bottom receivers distributed throughout the area.

A long-offset acquisition system includes a source vessel; a signal source coupled to the source vessel; and a long-offset streamer coupled to a survey vessel and including an aft-most receiver, an offset of the aft-most receiver being at least 12 km. A long-offset acquisition method includes towing a signal source with a source vessel; towing a first long-offset streamer with a survey vessel; and acquiring data with receivers of the first long-offset streamer. A long-offset acquisition method includes towing a signal source with a first survey vessel; towing a long-offset streamer with a second survey vessel, the long-offset streamer having a plurality of receivers; actuating the signal source while an offset between the signal source and at least one of the plurality of receivers is at least 15 km; and acquiring data with receivers of the long-offset streamer.

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 method and apparatus for generating a geophysical data product by a process of: acquiring standard-offset survey data for a subterranean formation with a standard-offset survey spread towed at a standard-offset spread depth; acquiring long-offset survey data for the subterranean formation with a long-offset streamer towed at a long-offset streamer depth; and assembling the long-offset survey data into a set of grouped-long-offset survey data characterized by a plurality of receiver groupings and a group length. A method, includes: towing a standard-offset survey spread at a standard-offset spread depth; acquiring standard-offset survey data for a subterranean formation with the standard-offset survey spread; towing a long-offset streamer with a vessel at a long-offset streamer depth; acquiring long-offset survey data for the subterranean formation with the long-offset streamer; and assembling the long-offset survey data into a set of grouped-long-offset survey data characterized by a plurality of receiver groupings and a group length.

The following disclosure relates to a system for generating velocity models of salt and subsalt formations. The system provides accurate velocities for both salt and subsalt formations. In some embodiments, the disclosure relies on the combination of three elements: the long offset between seismic source and seismic receiver node, the use of multiple seismic signals at different geographic locations, and the refraction of the seismic wave off of the basement of the earth's crust. By combining the multiple seismic signals with the fast basement, which is accessible due to the long offset of sources and receiver nodes, it is now possible to determine a more accurate seismic propagation velocity for salt and subsalt formations by using FWI-based refraction tomography.

A long offset land seismic survey spread includes a plurality of sensors within an area thereby defining a sensor receiver patch, a plurality of long offset sensor receivers outside of the receiver patch thereby surrounding the receiver patch and defining a sensor long offset area that is fee from sensor receivers that also defines a distance separating an external border of the sensor receiver patch and the long offset sensor receivers being a minimum offset distance that is a long offset distance.

A system and method for acquiring seismic streamer data is provided. Embodiments may include performing a marine seismic survey using an unmanned marine vessel having a power source configured to drive and provide propulsion to the unmanned marine vessel. Embodiments may further include acquiring one or more of long and ultra-long seismic survey data using a multi-dimensional seismic sensor array coupled with the unmanned marine vessel and providing the seismic survey data as a reduced data set that includes long and ultra long offsets.

The following disclosure relates to a system for generating velocity models of salt and subsalt formations. The system provides accurate velocities for both salt and subsalt formations. In some embodiments, the disclosure relies on the combination of three elements: the long offset between seismic source and seismic receiver node, the use of multiple seismic signals at different geographic locations, and the refraction of the seismic wave off of the basement of the earth's crust. By combining the multiple seismic signals with the fast basement, which is accessible due to the long offset of sources and receiver nodes, it is now possible to determine a more accurate seismic propagation velocity for salt and subsalt formations by using FWI-based refraction tomography.