Abstract: The present disclosure is directed to loading a helical conveyor for underwater seismic exploration. The system includes a case and a first conveyor having a helix structure provided within the case to support one or more ocean bottom seismometer (“OBS”) units. The case can include a first opening at a first end of the first conveyor and a second opening at a second end of the first conveyor. The system can include a base to receive at least a portion of the case. The system can include a second conveyor positioned external to the case that can move an OBS unit into the first opening at the first end of the first conveyor. The first conveyor can receive the OBS unit and direct the OBS unit towards the second opening at the second end of the first conveyor.

Abstract: A wireless seismic data acquisition unit with a wireless receiver providing access to a common remote time reference shared by wireless seismic data acquisition units in a seismic system. The receiver can replicate local version of remote time epoch to which a seismic sensor analog-to-digital converter is synchronized. The receiver can replicate local version of remote common time reference to time stamp local node events. The receiver can be placed in a low power, non-operational state over periods of time during which the unit continues to record seismic data, thus conserving unit battery power. The system corrects the local time clock based on intermittent access to the common remote time reference. The system corrects the local time clock via a voltage controlled oscillator to account for environmentally induced timing errors. The system provides a more stable method of correcting drift in the local time clock.

Abstract: Systems and methods of detecting marine seismic survey parameters are provided. A data processing system can obtain seismic data from seismic data acquisition units disposed on a seabed responsive to an acoustic signal propagated from an acoustic source through a water column. The data processing system can determine from the seismic data, a direct arrival time for the acoustic signal at each of the plurality of seismic data acquisition units, and can obtain an estimated depth value of each of the plurality of seismic data acquisition units and an estimated water column transit velocity of the acoustic signal. The data processing system can apply a depth model and a water column transit velocity model to the estimated depth value and to the estimated water column transit velocity determine an updated depth value and an updated water column transit velocity for each of the plurality of seismic data acquisition units.

Abstract: The present disclosure provides optical link management in a marine seismic environment. A first device can transmit, to a second device, a first optical transmission at a first output level. The first optical transmission can include a first packet corresponding to a network protocol. The first device can determine that the second device failed to receive the first packet via the first optical transmission. The first device can transmit, responsive to failure of the first optical transmission, a second optical transmission at a second output level different than the first output level. The second optical transmission can include a second packet corresponding to the network protocol. The first device can identify that the second packet was successfully received by the second link manager agent. The first device can establish, responsive to the identification that the second packet was successfully received, the second output level as a transmission output level for the first device.

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: A method of performing a seismic survey including: deploying nodal seismic sensors at positions in a survey region; activating a plurality of seismic sources; and using the nodal seismic sensors to record seismic signals generated in response to the activation of the plurality of signals.