Abstract: A system to improve calibration of geophone and hydrophone pairs is described. The system generates first and second phase shifted data by applying a first and second phase shift to first seismic data acquired by the geophone. The system generates a first upgoing wavefield by summing the first phase shifted data and second seismic data acquired by the hydrophone, and a second upgoing wavefield by summing the second phase shifted data and the second seismic data. The system generates a first downgoing wavefield from a difference of the first phase shifted data and the second seismic data, and a second downgoing wavefield from a difference of the second phase shifted data and the second seismic data. The system determines ratios of the upgoing wavefields and the downgoing wavefields for each phase shift to identify the highest ratio, and selects the phase shift corresponding to the highest ratio for calibration.

Abstract: The present disclosure relates to a method of processing seismic signals comprising: receiving a set of seismic signals, applying a wavelet transformation to the set of signals and generating transformed signals across a plurality of scales. Then for each scale determining coherence information indicative of the transformed signals and generating a comparison matrix comparing the transformed signals, then outputting seismic attribute information based on combined coherence information.

Abstract: Systems and methods of performing a seismic survey are described. The system can receive seismic data. The system receives seismic data from one or more seismic data sources. The system propagates the seismic data forward in time through a subsurface model to generate a first wavefield. The system propagates the seismic data backward in time through the subsurface model to generate a second wavefield. The system combines the first wavefield with the second wavefield using a time gate imaging condition to produce subsurface images and image gathers.

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: Systems and methods for retrieving seismic data acquisition units from an underwater seismic survey are provided. The system includes an underwater vehicle with a base and an underwater vehicle interlocking mechanism. The underwater vehicle receives environmental information and identifies a seismic data acquisition unit located on an ocean bottom. The underwater vehicle obtains an indication to perform a non-landing retrieval operation. The underwater vehicle sets a position of the underwater vehicle interlocking mechanism to extend away from the base of the underwater vehicle. The underwater vehicle retrieves the seismic data acquisition unit by coupling the underwater vehicle interlocking mechanism with a seismic data acquisition unit interlocking mechanism. The underwater vehicle stores the seismic data acquisition unit and then sets the underwater vehicle interlocking mechanism in a second position to perform the non-landing retrieval operation for a second seismic data acquisition unit.

Abstract: Systems and methods of deploying seismic data acquisition units from a marine vessel are disclosed. The system can include a mechanical attachment device comprising a cavity formed by interlocking a first member and a second member. Protrusions located on the first member and second member can increase the coefficient of friction between a rope and the mechanical attachment device responsive to an increase in tension on the rope. A lanyard can couple a seismic data acquisition unit to the mechanical attachment device.

Abstract: Methods and systems for minimizing RMS travel time error in a seismic data acquisition. Field measurements of source and receiver coordinates, speed of sound in water as a function of depth and time, receiver timing, and clock drift are first collected. The seismic data is then examined to measure travel time from each source to each receiver. A model travel time is computed based on the field measurements. By iteratively perturbing at least one of the field measured data using a look-up table and calculating the travel time after each perturbation until an acceptable RMS error has been achieved, conditioned seismic data that takes into account the dynamic nature of the water column will provide the basis for creating an accurate seismic map that is unaffected by the changing water conditions.

Abstract: The present disclosure is directed to detecting subsurface features via a seismic survey. A system can obtain seismic data from nodes separated from each other by at least a threshold distance on a ground surface. The seismic data can include image trace data based on field trace data detected from each of the plurality of seismic data acquisition units. The system retrieves a sample interval and a parameter. The system configures a bandlimited binning function with the sampling interval and the predetermined parameter. The system applies the bandlimited binning function to a plurality of image traces of the image trace data to generate a bandlimited angle gather value for a bin in an angle gathers grid. The system generates an image based on the angle gathers grid and provides the image for display.

Abstract: A computing system and method for determining the x, y energy receiver (node) positions regardless of the angle at which the energy was released from the source. The process and computing system involves an iterative looping technique that is executed in data processing software wherein an initial model position based on, in essence, a best guess as to a node's location, followed with the iterative process of statistically comparing model data to actual data and then adjusting the model position by some predetermined amount and comparing this new result to the actual data to determine if the newly adjusted position is statistically better or worse than the originally selected position assumption. The process can be repeated using continuously smaller distance adjustments to the previously determined best position. Once satisfied that the true best position has been achieved, the processing can cease and the XY position data may be used in the normal course of generating seismic maps.

Abstract: Systems and methods of performing a seismic survey are described. The system can receive seismic data. The system receives seismic data from one or more seismic data sources. The system propagates the seismic data forward in time through a subsurface model to generate a first wavefield. The system propagates the seismic data backward in time through the subsurface model to generate a second wavefield. The system combines the first wavefield with the second wavefield using a time gate imaging condition to produce subsurface images and image gathers.

Abstract: The present disclosure relates to a method of processing seismic signals comprising: receiving a set of seismic signals, applying a wavelet transformation to the set of signals and generating transformed signals across a plurality of scales. Then for each scale determining coherence information indicative of the transformed signals and generating a comparison matrix comparing the transformed signals, then outputting seismic attribute information based on combined coherence information.

Abstract: Apparatus and methods to operationally deploy land-based seismic nodes. An autonomous or semi-autonomous vehicle includes apparatus for placing, monitoring, testing, servicing, and collecting nodes in a harsh environment such as, e.g., tundra or desert. Associated methods of node deployment and retrieval are disclosed including a ‘rollover deployment.

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: The present disclosure is directed to a helical conveyor for underwater seismic exploration. The system can include a case having a cylindrical portion. A cap is positioned adjacent to a first end of the case. A conveyor having a helix structure is provided within the case. The conveyor can receive an ocean bottom seismometer (“OBS”) unit at a first end of the conveyer and transport the OBS unit via the helix structure to a second end of the conveyor to provide the OBS unit on the seabed to acquire the seismic data.

Abstract: The present disclosure is directed to underwater seismic exploration with a helical conveyor and skid structure. The system can include an underwater vehicle comprising a sensor to identify a case having a hydrodynamic shape, wherein the case stores one or more ocean bottom seismometer (“OBS”) units. The underwater vehicle includes an arm. The underwater vehicle includes an actuator to position the arm in an open state above a cap of the case, or to close the arm. The underwater vehicle can move the arm to a bottom portion of the case opposite the cap. An opening of the case can be aligned with the conveyor of the underwater vehicle. The conveyor can receive, via the opening of the case, a first OBS unit of the one or more OBS units. The conveyor can move the first OBS unit to the seabed to acquire seismic data from the seabed.

Abstract: The present disclosure is directed to a helical conveyor for underwater seismic exploration. The system can include a case having a cylindrical portion. A cap is positioned adjacent to a first end of the case. A conveyor having a helix structure is provided within the case. The conveyor can receive an ocean bottom seismometer (“OBS”) unit at a first end of the conveyer and transport the OBS unit via the helix structure to a second end of the conveyor to provide the OBS unit on the seabed to acquire the seismic data. The system can include a propulsion system to receive an instruction and, responsive to the instruction, facilitate movement of the case.

Abstract: A self-contained, wireless seismic data acquisition unit having a cylindrically shaped case with smooth side walls along the length of the case. A retaining ring around the circumference is used to secure the cylindrical upper portion of the case to the cylindrical lower portion of the case. Interleaved fingers on the upper portion of the case and the lower portion of the case prevent the upper portion and the lower portion from rotating relative to one another. Ruggedized external electrical contacts are physically decoupled from rigid attachment to the internal electrical components of the unit utilizing electrical pins that “float” relative to the external case and the internal circuit board on which the pins are carried. The seismic sensors in the unit, such as geophones, and the antennae for the unit are located along the major axis of the cylindrically shaped case to improve fidelity and timing functions.

Abstract: A system to deploy seismic sensors in a marine environment is provided. The system includes a seismic sensor transfer device to house and transport a plurality of seismic sensors. The seismic sensor transfer device is deployed from a vessel. The system includes a propulsion system of the seismic sensor transfer device to receive an instruction and move, responsive to the instruction, the seismic sensor transfer device. The system includes an underwater vehicle that transfers at least one of the plurality of seismic sensors from the seismic sensor transfer device to the underwater vehicle. The underwater vehicle operates at a second speed different from a first speed at which the vessel operates. The underwater vehicle places the at least one seismic sensor on a seabed.

Abstract: The present disclosure is directed to a skid structure for underwater seismic exploration. The system can include an underwater vehicle comprising a skid structure. A conveyor is provided in the skid structure. The conveyor includes a first end and a second end opposite the first end. A capture appliance is provided at the first end of the conveyor. The capture appliance includes an arm to close to hold a case storing one or more ocean bottom seismometer (“OBS”) units, and to open to release the case. The capture appliance includes an alignment mechanism to align an opening of the case with the first end of the conveyor. A deployment appliance can be at the second end of the conveyor. The deployment appliance can place an OBS unit of the one or more OBS units onto the seabed to acquire seismic data from the seabed.

Abstract: An autonomous underwater vehicle (AUV) including a deployable anchor and a method for operating an AUV having a deployable anchor in a hover mode.