HR: 1340h
AN: OS13B-0531    [Abstracts]
TI: In-Situ Isotope Ratiometer for Hydrothermal Effluent Analysis
AU: * Gupta, M
EM: m.gupta@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: Owano, T
EM: t.owano@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: Baer, D S
EM: d.baer@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: Provencal, R A
EM: r.provencal@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: Ricci, K
EM: k.ricci@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: O'Keefe, A
EM: a.okeefe@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94043 United States
AU: Flynn, M
EM: mflynn@mail.arc.nasa.gov
AF: NASA Ames Research Center, MS 239-15 , Moffett Field, CA 94035 United States
AU: Holland, P
EM: pholland@thorleaf.com
AF: Thorleaf Research Incorporated, 5552 Cathedral Oaks Rd., Santa Barbara, CA 93111 United States
AB: Deep-sea hydrothermal vents provide unique access to water that has been trapped beneath the ocean floor for extended periods of time. Researchers have speculated that a Subsurface Lithotropic Microbiological Ecosystem (SLiME) may exist in this stagnant environment, and therefore desire to study hydrothermal vent effluents for indication of biogenic activity. Specifically, the carbon isotope ratio of methane and carbon dioxide emanating from such vents can provide decisive evidence of such a SLiME. Current technology involves obtaining effluent samples, transporting them from the ocean floor, and examining their degassed constituents with an Isotope Ratio Mass Spectrometer (IRMS). In practice, this procedure has led to contamination and severely limits the number of samples studied. We will report on the development of an in-situ optical analyzer to measure the carbon isotope ratio in both methane and carbon dioxide emanating from deep-sea hydrothermal vents. This analyzer degasses water at high pressure and then employs Off-Axis Integrated Cavity Output Spectroscopy to determine the carbon isotope ratios to better than 0.1%, sufficient to provide evidence of biological activity. Results of preliminary, laboratory testing will be divulged that involved the degassing of gaseous samples and subsequent removal of water vapor and hydrogen sulfide. Final deep-sea packaging and deployment opportunities will also be presented.
DE: 4820 Gases
DE: 4832 Hydrothermal systems
DE: 4294 Instruments and techniques
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting