Abstract: A method and apparatus for handling of sensor capsules and their inner components during deployment and retrieval of a seismic cable into the sea by a vessel where the seismic cable includes seismic node casings to contain the sensor capsules when the seismic cable is in the sea. The method includes the following steps: withdrawing a sensor capsule from a sensor capsule storage; withdrawing a battery unit from a battery unit storage; withdrawing a control unit from a docking station; combining the control unit and battery unit into a control/battery unit; inserting the control/battery unit into the sensor capsule and closing the sensor capsule; and loading the sensor capsule into a seismic node casing.

Abstract: A cleaning apparatus (100) for an ocean bottom cable (19) including a plurality of node casings (5), each containing at least one sensor capsule (9). During retrieval, an initial flushing device flushes the assembled cable with seawater before the capsules (9) are separated from the casings (5) in a loading/unloading apparatus (300). A washing tunnel (110) is configured to flush the sensor capsule (9) with water supplied from a freshwater tank (115) through a waterfeed pipe (117). Preferably, the cleaning apparatus also comprises a secondary flushing device for flushing the components with seawater after separation, and a drying tunnel (120). Separate conveyors convey the sensor capsules (9) and the node casings (5) to their respective destinations, such that each component may be flushed in seawater and/or freshwater and/or dried as required. The cleaning apparatus is optimized to use a minimum of freshwater and energy.

Abstract: An apparatus (100) for deploying and retrieving seismic nodes (200) comprises a towing connection (101) connecting the apparatus (100) to a towing cable (10) running from a towing vessel; vertical control means (125; 5; 120, 12) for adjusting a height over the seafloor by means of the towing cable (10); horizontal control means (125; 130-133) for adjusting a horizontal position according to the desired path and deployment and retrieval means (151; 160, 170, 180) for deploying and receiving nodes (200) connected to a wire (150) at predetermined intervals along the path. The deployment means are preferably configured to deploy the nodes (150) without substantial pull from the previously deployed wire (150).

Abstract: A cleaning apparatus (100) for an ocean bottom cable (19) including a plurality of node casings (5), each containing at least one sensor capsule (9). During retrieval, an initial flushing device flushes the assembled cable with seawater before the capsules (9) are separated from the casings (5) in a loading/unloading apparatus (300). A washing tunnel (110) is configured to flush the sensor capsule (9) with water supplied from a freshwater tank (115) through a waterfeed pipe (117). Preferably, the cleaning apparatus also comprises a secondary flushing device for flushing the components with seawater after separation, and a drying tunnel (120). Separate conveyors convey the sensor capsules (9) and the node casings (5) to their respective destinations, such that each component may be flushed in seawater and/or freshwater and/or dried as required. The cleaning apparatus is optimized to use a minimum of freshwater and energy.

Abstract: The invention relates to a seismic node (100), comprising at least one seismic sensor with associated electronics, a primary oscillator (106) for timing sensor signals, a reference oscillator (104), a memory, a power source, a switch (102) for turning the reference oscillator on and off, and a processor (112) for digitizing sensor signals and storing them in the memory, calibrating a frequency of the primary oscillator (106) based on the frequency of the reference oscillator (104), and turning the reference oscillator on and off.

Abstract: An apparatus (100) for deploying and retrieving seismic nodes (200) comprises a towing connection (101) connecting the apparatus (100) to a towing cable (10) running from a towing vessel; vertical control means (125; 5; 120, 12) for adjusting a height over the seafloor by means of the towing cable (10); horizontal control means (125; 130-133) for adjusting a horizontal position according to the desired path and deployment and retrieval means (151; 160, 170, 180) for deploying and receiving nodes (200) connected to a wire (150) at predetermined intervals along the path. The deployment means are preferably configured to deploy the nodes (150) without substantial pull from the previously deployed wire (150).

Abstract: A method and apparatus for handling of sensor capsules and their inner components during deployment and retrieval of a seismic cable into the sea by a vessel where the seismic cable includes seismic node casings to contain the sensor capsules when the seismic cable is in the sea. The method includes the following steps: withdrawing a sensor capsule from a sensor capsule storage; withdrawing a battery unit from a battery unit storage; withdrawing a control unit from a docking station; combining the control unit and battery unit into a control/battery unit; inserting the control/battery unit into the sensor capsule and closing the sensor capsule; and loading the sensor capsule into a seismic node casing.

Abstract: The invention relates to a seismic node (100), comprising at least one seismic sensor with associated electronics, a primary oscillator (106) for timing sensor signals, a reference oscillator (104), a memory, a power source, a switch (102) for turning the reference oscillator on and off, and a processor (112) for digitizing sensor signals and storing them in the memory, calibrating a frequency of the primary oscillator (106) based on the frequency of the reference oscillator (104), and turning the reference oscillator on and off.