University of North Florida
Browse the Citations

Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

View Stuart Chalk's profile on LinkedIn


Classification: Environmental -> water -> ice

Citations 3

"Ultratrace Analysis Of Antarctic Snow And Ice Samples Using High Resolution Inductively Coupled Plasma Mass Spectrometry"
J. Anal. At. Spectrom. 1998 Volume 13, Issue 5 Pages 463-468
Ashley T. Townsend and Ross Edwards

Abstract: High resolution ICP-MS was used to determine the concentrations of Al, Sc, V, Mn, Fe, Co, Pb and Bi in snow and ice from Antarctica. To overcome some potentially problematic spectral interferences, measurements were acquired in both low and medium resolution modes. Small sample volumes were analyzed using a microconcentric nebulizer. After rigorous instrument cleaning and sample preparation, detection levels in the low and sub-pg g-1 range (0.3-48 pg g-1) were found for all elements. Concentration. values were determined for a continental snow, sea ice snow and a representative ice core. Concentration. ranges for all snow samples (n = 25) were (in pg g-1): Al (30-2000), V (2-16), Mn (2-30) and Fe (30-1500), while Sc and Co were typically below detection or blank limits. The ice core sample had Al, Mn, Fe and Pb concentrations of 90, 7, 110 and 1 pg g-1, respectively, while Sc, V, Co and Bi could not be quantified (below detection or blank limits). The reliability of the analytical method for Fe was confirmed by flow injection analysis with spectrophotometric detection.
Aluminum Scandium Vanadium Manganese Iron Cobalt Lead Bismuth Mass spectrometry Interferences Method comparison

"Iron In Ice Cores From Law Dome, East Antarctica: Implications For Past Deposition Of Aerosol Iron"
Ann. Glaciol. 1998 Volume 27, Issue 1 Pages 365-370
R. Edwards, P.N. Sedwick, Vin Morgan, C.F. Boutron and S. Hong

Abstract: Total-dissolvable iron has been measured in sections of three ice cores from Law Dome, East Antarctica, and the results used to calculate atmospheric iron deposition over this region during the late Holocene and to provide a preliminary est. of aerosol iron deposition during the Last Glacial Maximum (LGM). Ice-core sections dating from 56-2730 BP (late Holocene) and ~18 000 BP (LGM) were decontaminated using trace-metal clean techniques, and total-dissolvable iron was determined in the acidified meltwaters by flow injection analysis. Our results suggest that the atmospheric iron flux onto the Law Dome region has varied significantly over time-scales ranging from seasonal to glacial-interglacial. The iron concentrations in ice-core sections from the past century suggest (1) a 2-4-fold variation in the atmospheric iron flux over a single annual cycle, with the highest flux occurring during the spring and summer, and (2) a nearly 7-fold variation in the annual max. atmospheric iron flux over a 14 year period. The average estimated atmospheric iron flux calculated from our late-Holocene samples is 0.056-0.14 mg m-2 a-1, which agrees well with Holocene flux estimates derived from aluminum measurements in inland Antarctic ice cores and a recent order-of-magnitude estimate of present-day atmospheric iron deposition over the Southern Ocean. The iron concentration. of an ice-core section dating from the LGM was more than 50 times higher than in the late-Holocene ice samples. Using a snow-accumulation rate estimate of 130 kg m-2 a-1 for this period, we calculated 0.87 mg m-2 a-1 as a preliminary estimate of atmospheric iron deposition during the LGM, which is 6-16 times greater than our average Late-Holocene iron flux. Our data are consistent with the suggestion that there was a significantly greater flux of atmospheric iron onto the Southern Ocean during the LGM than during the Holocene.

"Continuous Analysis Technique For Trace Species In Ice Cores"
Environ. Sci. Technol. 1994 Volume 28, Issue 2 Pages 204-209
Andreas Sigg, Katrin Fuhrer, Martin Anklin, Thomas Staffelbach, and Daniel Zurmuehle

Abstract: A continuous melting technique, combined with continuous-flow analysis was developed for in situ determination of chemical species in ice cores. A cross-section of 1.8 x 1.8 cm2 of the core was required for the simultaneous analysis of at least four species. This subcore, cut with a bandsaw, was melted continuously from one side and the melt water was split into two fractions. The inner fraction was used for the determination of species susceptible to contamination, e.g. formaldehyde, ammonium and Ca(II). The outer fraction was analyzed for species not susceptible to contamination, e.g., H2O2. Analysis was by continuous-flow systems, using valves to switch between sample and calibration solution (full details and diagrams given). The spatial resolution was of the order of 1 cm. Results are discussed.
Formaldehyde Calcium(2+) Ammonium