In-situ chemical sensors for detecting and exploring ocean floor hydrothermal vents : report of a workshop : technical report

Abstract

Researchers and engineers, from academia, government, and industry, met and discussed the feasibility of using state-of-the-art laboratory technology for in-situ chemical measurements in the deep ocean, in and around active submarine hydrothermal systems. The concept of an autonomous benthic explorer (SENTRY) was presented to illustrate some of the constraints which must be kept in mind when adapting laboratory analytical tools to the deep ocean. A concensus was reached that some existing technologies either are being, or can be, adapted for in-situ measurement, in the near future, at reasonable cost . For many analytical techniques, minimal basic research will be required , and laboratory and in-situ testing represent the bulk of the work to be performed. A selection of analytical techniques appear particularly ready to undergo testing and transformations for in-situ measurements, including: electroplating, vol tame try, potentiometric glass electrodes, and fiber optic technologies. Other techniques, such as in-situ Mass Spectrometry, do not appear to meet the criterias of technological readiness for in-situ deployment . Some technologies already being utilized or under development for use in the deep ocean include, for example: CO2, O2, H2, H2S, CH4 sensors, voltametry for the determination of sulfur chemical speciation, fiber optic sensors for pH determination, and automated chemical microlaboratories for a wide variety of applications. These techniques, however, require further research for long-term deployment and their ability to perform at high temperature, as encountered around submarine active hydrothermal systems.