HR: 0800h
AN: H41C-0423    [Abstracts]
TI: Development and Validation of a Field-Deployable Optical Spectrometer for Real-Time, Natural Abundance Measurements of O and H Isotopes of Water
AU: * Gupta, M
EM: m.gupta@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: Owano, T
EM: t.owano@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: Baer, D
EM: d.baer@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: Provencal, R
EM: r.provencal@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: Ricci, K
EM: k.ricci@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: O'Keefe, A
EM: a.okeefe@lgrinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041 United States
AU: Kendall, C
EM: ckendall@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road MS 434, Menlo Park, CA 94025 United States
AU: Doctor, D
EM: dhdoctor@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road MS 434, Menlo Park, CA 94025 United States
AU: Rollog, M
EM: merollog@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road MS 434, Menlo Park, CA 94025 United States
AU: Silva, S
EM: srsilva@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road MS 434, Menlo Park, CA 94025 United States
AU: McDonnell, J
EM: Jeffrey.McDonnell@oregonstate.edu
AF: Oregon State University, Dept. of Forest Engineering, Corvallis, OR 97331 United States
AB: Water isotopes provide critical knowledge about the history and age of water supplies, degree of water mixing, location of water recharge, and velocity of ground water flow. Current technology involves collecting individual water samples, transporting them to a laboratory, and quantifying the isotope ratios via an Isotope Ratio Mass Spectrometer (IRMS). For water vapor samples, the issue is further complicated by the need to first freeze and preconcentrate the sample prior to analysis. In practice, this procedure has made long-term continuous monitoring of water supplies prohibitively time-consuming. We will report on the development and independent validation of a novel water isotope ratiometer based on cavity-enhanced laser absorption spectroscopy techniques (Off-Axis Integrated Cavity Output Spectroscopy) to quantify 18O/16O, 17O/16O, and D/H to better than 0.3 per mil, 0.5 per mil, and 2 per mil respectively. The analyzer provides continuous monitoring of either ambient water vapor (without preconcentration) or repeatedly injected liquid samples. Independent validation of the instrument's capabilities will be presented and results from recent field tests will be discussed.
DE: 1895 Instruments and techniques: monitoring
SC: Hydrology [H]
MN: Fall Meeting 2005