Physics
Scientific paper
Aug 1990
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1990georl..17.1303l&link_type=abstract
Geophysical Research Letters (ISSN 0094-8276), vol. 17, Aug. 1990, p. 1303-1306.
Physics
12
Carbon Monoxide, Carbon 14, Cosmic Rays, Ice Formation, Radioactive Isotopes, Carbon Dioxide, Chronology, Neutrons
Scientific paper
Radiocarbon is produced in situ in ice by nuclear spallations of oxygen by cosmic ray neutrons. As the firn accumulates, it acquires a predictable concentration of in situ C-14, inversely proportional to the rate of accumulation. Most of this production occurs when the amount of overlying ice is less than (2-3) Lambda, where lambda is the absorption mean free path for cosmic radiation in ice, about 150 g/sq cm, i.e. within the top 10 m. In most accumulation areas, this is firn. In situ produced C-14 is added to the firn as it accumulates, and is not expected to be lost by diffusion. During the firn-ice transition, atmospheric CO2 is trapped, adding (C-14)02 to the ice. The signature of in situ C-14 is however not obliterated since about 60 percent of in situ C-14 is instantly oxidized to (C-14)O in the ice. The results available to date are discussed, and it is proposed that this in situ (C-14)O can be used to determine ice accumulation rates back to 40,000 yrs in the past.
Lal Devendra
Timothy Jull A. J.
No associations
LandOfFree
On determining ice accumulation rates in the past 40,000 years using in situ cosmogenic C-14 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On determining ice accumulation rates in the past 40,000 years using in situ cosmogenic C-14, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On determining ice accumulation rates in the past 40,000 years using in situ cosmogenic C-14 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1127362