Abstract
We have analysed 13 samples of trapped air in recent (<2200 years B.P.) ice from eight sites. The average δ15N of N2 and δ18O of O2 in samples from the various ice cores ranged from +0.05 to +0.41 ‰ and from +0.18 to +1.1 ‰, respectively. The heavy isotope enrichments are apparently due to gravitational settling accompanying diffusive equilibrium between the base of the firn and the overlying atmosphere. The δO2/Ar and δN2/Ar values ranged from -9.2 to +1.0‰ and from -4.8 to +4.6‰, respectively. The differences between the elemental composition of ice core trapped gases and air result from gravitational fractionation, as well as separation of O2 and Ar relative to N2 during either bubble close-off or retrieval and storage of the ice core. -from Authors
Original language | English (US) |
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Pages (from-to) | 5137-5150 |
Number of pages | 14 |
Journal | Journal of Geophysical Research |
Volume | 94 |
Issue number | D4 |
DOIs | |
State | Published - Jan 1 1989 |
All Science Journal Classification (ASJC) codes
- Geophysics
- Forestry
- Oceanography
- Aquatic Science
- Ecology
- Water Science and Technology
- Soil Science
- Geochemistry and Petrology
- Earth-Surface Processes
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science
- Palaeontology