A PISTON CORER FOR RECOVERY OF DEEP OCEAN SEDIMENTS UNDER PRESSURE
A corer has been designed to sample and recover deep marine sediments without loss of hydrostatic pressure. The device consists of the piston corer device of classical design; a pressure-retaining core module (1.5 m long) with two high-pressure (60-80MPa) self-cleaning spherical valves at either end for pressure sealing the sample and an acoustic control system for monitoring the performance of the corer during operation and commanding the closure of the valves. The core barrel is modular so that the pressure section can be placed in any position along the 6m core string. Sediment sampled in adjacent sections depressurises, thus allowing a direct comparison between this and the sediment maintained under pressure. During sediment penetration, the corer control unit, housed in the tail section, detects the passage of the piston past two ultrasonic detectors, activating the closure of the two spherical valves. Field tests of the control unit have verified its ability to perform successfully when subjected to the dynamic forces of a coring operation.
Bibliographic Reference: ARTICLE: MARINE GEOTECHNOLOGY, VOL. 8 (1989) PP. 69-80
Record Number: 1989128071500 / Last updated on: 1990-10-01
Available languages: en