Development of a new hybrid Raman insertion probe for deep-ocean science

A new deep-sea hybrid Raman insertion probe (RiP) has been developed by the Institute of Oceanology, Chinese Academy of Sciences (IOCAS) and the Ocean University of China (OUC) for the detection of the hydrothermal vent, cold seep fluid and sediment pore water geochemistry. The novel probe can work at temperature range from 0 to 450 °C with water depth to 4500 m. The RiP system had been separated to three main parts: the probe, the sucking filtration system, and the Raman spectra collector, which in a custom designed 6000m titanium pressures housing. It can be power supplied, controlled and field deployed by ROV (remotely operated vehicle) Faxian. The RiP system includes three different kinds of probes for different sample and work situation, and has variable length from 10 to 60 cm. A deep-sea laser Raman spectrometer has been developed as the Raman spectra collector in RiP system. The spectral coverage is from 100 to 4325 cm
^-1
, with spectral resolution about 2 cm
^-1
. With different optic and tip set up, it can be directly inserted into the high temperature black smoker in the hydrothermal area for the geochemistry of the hydrothermal vent fluids up to 450 °C (RiP-Hv). It can be used for cold seep fluids geochemistry (RiP-Cs). It also can be deployed as a pore water Raman probe (RiP-Pw) for the sediment pore water profiles, such as CH
₄
, H
₂
S, HS
^-
, SO
₄
^2-
, and pH.