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1999 Projects

Current Projects

Green_Ball.gif (257 bytes) Benthic processes
Green_Ball.gif (257 bytes) Midwater research
Green_Ball.gif (257 bytes) Upper ocean biogeochemistry
Green_Ball.gif (257 bytes) New research platforms
Green_Ball.gif (257 bytes) ROV improvements
Green_Ball.gif (257 bytes) Mooring improvements
Green_Ball.gif (257 bytes) New in-situ Instruments
Green_Ball.gif (257 bytes) Information management and archiving
Green_Ball.gif (257 bytes) Education and outreach
Green_Ball.gif (257 bytes) 1998 Projects
Green_Ball.gif (257 bytes) 1997 Projects


1999 Projects: New in-situ Instruments

Instrumentation for studies on redox-active chemical species

Project lead/ manager: Carole Sakamoto
Project team: James Barry, Kurt Buck, Hans Jannasch, and Josh Plant

This project focuses on advancing deep-sea research by optimizing two methodologies for measuring hydrogen sulfide and other redox (reduction-oxidation) -active chemical species. This project joins MBARI’s chemical and biological research groups studying cold seeps to address the two basic questions: How are the distribution and abundance of seep organisms related to environmental sulfide levels, and how does sulfide distribution vary over time?

The critical technologies for approaching answers to these questions are robust sensors capable of measuring sulfide at sufficient resolution to distinguish the spatial and temporal variability of cold-seep environments. We will pursue two approaches this problem: continuing development of the sulfide OsmoAnalyzer and applying recent advances in fast-scan voltammetry using solid-state microelectrodes for measuring a suite of redox species (HS-, O2, Mn2+, Fe2+). The development of two sensors is necessary because measurements of hydrogen sulfide need to be made at various concentrations (ranging from Ámol/L to mmol/L) and time scales (from seconds to months), and no single method is appropriate for assessing both the temporal and spatial variability. In the future these instruments could be modified for ROV deployment at cold-seep sites and at low-temperature hydrothermal vents. The ultimate goal of this work is to advance our understanding of geochemical fluxes and biotic interactions involving hydrogen sulfide and other redox-active species in environments such as cold seeps and low-temperature hydrothermal vents by developing instrumentation for making measurements in situ.

Next: Low-power, high-performance instrument controller

Last updated: 07 October 2004