A deployment module according to the present application enables both compact stowage of a sensor array and expansion of the sensor array into a three-dimensional volumetric array shape that enables improved directionality of the sensors during operation. The deployment module includes a support shell that is configured to retain a cable of the sensor array separately from sensors of the sensor array and an expandable deployment body formed of a superelastic shape memory alloy that uses superelasticity and stored energy for deployment of the sensor array. During deployment, the deployment body is removed from the support shell and the sensors are subsequently pulled out of the support shell. The deployment body then expands and holds the cable to retain the three-dimensional volumetric shape of the deployed array.

This disclosure presents processes and systems for estimating a source wavelet from seismic data recorded in a seismic survey of a subterranean formation. In one aspect, a base wavelet is determined based on recorded seismic traces obtained in a seismic survey of a subterranean formation. Processes and systems include a phase-only wavelet based on the base wavelet and the recorded seismic data. An estimated source wavelet is obtained by convolving the base wavelet with the phase-only wavelet. Properties of the subterranean formation are determined based on the estimated source wavelet and the recorded seismic data.

A vessel system includes a hull configured to provide buoyancy, one or more seismic sources configured to generate seismic energy, and a deployment apparatus configured to deploy the seismic sources from the hull to a water body or water column. A control system can be configured to operate the deployment apparatus, in order to deploy the seismic sources.

Techniques are described for utilizing far offset impulsive source activations in various contexts, including when performing marine seismic surveys, when manufacturing a geophysical data product in conjunction with such surveys, or when generating an image of geological features of a subsurface. According to some embodiments, near offset impulsive source activations are caused in a body of water at each of a plurality of near offset shot points, and composite far offset impulsive source activations are caused in the body of water at each of a plurality of far offset shot points. Each of the composite far offset impulsive source activations comprises a succession of component impulsive source activations occurring over a far offset shot length. The far offset shot length is short enough to satisfy a stationary source assumption for frequencies at or below a maximum frequency of interest for the far offset shot points.

A seismic node deployment system comprises a cable supply with one or more seismic nodes configured for coupling to the cable at one or more attachment locations for deployment to a water column. A node attachment system is configured to drive a portion of the cable into periodic or reciprocal motion so that the attachment speed is substantially reduced relative to the speed at which the cable is deployed.

A method and apparatus for operating a single source vessel along a survey path, the source vessel towing a source and a first plurality of streamers; operating a streamer vessel along the survey path, the streamer vessel towing a second plurality of streamers; actuating the source; acquiring near-offset data with a first plurality of receivers; and acquiring long-offset data with a second plurality of receivers. A system includes a source vessel coupled to: a source; and a near-offset survey spread; a streamer vessel coupled to a long-offset survey spread, wherein a streamer spacing density of the long-offset survey spread is no greater than a streamer spacing density of the near-offset survey spread; and a survey plan including navigation information for the source vessel and the streamer vessel, wherein the navigation information directs the source vessel and the streamer vessel along a common survey path while the source is actuated.

An air gun for generating seismic waves in a marine environment includes a cylindrical body configured to hold compressed air and having plural air ports for releasing the compressed air from inside the cylindrical body, the cylindrical body extending along a longitudinal axis X, and an extension member attached externally to the body and extending along a radial axis R, which is perpendicular to the longitudinal axis X. The extension member promotes ambient water flowing inside an air bubble generated when the compressed air is released outside the body.

A stable towable submersible device includes a rigid body that is towed at a positive pitch angle relative to the device's direction of motion. An acoustic projector housing extends vertically from the rigid body. When the rigid body rolls about its roll axis, which is tilted at the positive pitch angle, the acoustic projector rolls about the roll axis changing the acoustic projector's angle of attack relative to the direction of motion and generates a restoring force causing the acoustic projector to rotate back to a generally vertical orientation.

An attachment system for releasably attaching a sensor node to a cable when in a coupled state includes a clamp base and a clamp grip. The clamp base is fixed to a surface of the sensor node. The clamp base further includes a latch that is biased in a latched position when the attachment system is in both the coupled state and an uncoupled state. The clamp grip is pivotably attached the clamp base and biased in an open position when the attachment system is in the uncoupled state. The clamp grip is secured to the clamp base by the latch when the attachment system is in the coupled state.

Methods and systems described herein are directed to determining properties of a subterranean formation using an acoustic wave-equation with a novel formulation in terms of a velocity model and a reflectivity model of the subterranean formation. The acoustic wave equation may be used with full-waveform inversion to simultaneously build velocity and reflectivity models of a subterranean formation. The velocity and reflectivity models may be employed for quantitative interpretation. The velocity and reflectivity models may be employed to determine impedance and density of the subterranean formation for prospectivity assessment. The acoustic wave equation may be also used with least-squares reverse time migration in the image or data domains, to build a reflectivity model of the subterranean formation with enhanced resolution and amplitude fidelity. The velocity and reflectivity models reveal the structure and lithology of features of the subterranean formation and may reveal the presence of oil and natural gas reservoirs.