The DEAFS (Deep-Sea Autonomous Experimental Facility System) represents a significant advancement in the study of deep-sea ecosystems. One of the core tools within this system is IBIS, developed by Ifremer, which combines isobaric and isothermal sampling with a submersible designed for the study of microorganisms in hydrothermal fluids associated with deep-sea marine ecosystems (up to 6000 meters below the sea surface). The tool can also record the pressure and temperature of the sample to evaluate the quality of the sampling and its conditioning. Additionally, it allows for sub-sampling and incubating fluid samples without depressurization. This project, funded by the Carnot Institute, is the result of a collaboration between Ifremer’s RDT unit for the design and development of IBIS integration on the Nautile and Victor submersibles, and GENAVIR’s DSM team for submersible operability. Top Industrie was responsible for manufacturing the pressure vessels and the multiplier. The project also benefited from the expertise of the hyperbaric team at MIO (Aix-Marseille University).
High-Pressure Serial Sampler (HPSS)
The HPSS is a Sea-Bird carousel equipped with eight 500 ml high-pressure bottles, where hydrostatic pressure is continuously monitored during filling, recovery, and incubation. Fluorescent or radioisotopic tracers can be injected into each bottle.
Key Features
- Continuous Monitoring:
Hydrostatic pressure is continuously monitored inside the high-pressure bottles during sampling, ensuring the integrity of the samples. - Sub-Sampling Capabilities:
Sub-samples can be extracted without decompressing the main culture, enabling time-series experiments. - High-Pressure Serial Sampler Unit (HPSU):
The HPSU is configured for sample filling, with the fill valve operated by the scientist onboard the vessel. When the fill valve is opened, natural hydrostatic pressure pushes the floating piston down, allowing seawater to enter the upper chamber of the HPSU. Distilled water is flushed from the lower chamber of the syringe into the exhaust reservoir using a nozzle (0.01” catheter) that acts as a hydraulic brake.
Components of an HPSU
- High-Pressure Bottle (HPB):
Mounted on a polypropylene frame suitable for a Sea-Bird carousel. - Pressure Sensor:
Monitors hydrostatic pressure inside the HPB’s exhaust reservoir. - Pressure Accumulator:
Compensates for material deformation under high hydrostatic pressure.
