14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica

Details 14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica 14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica

Jul 1993

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993metic..28r.376j&link_type=abstract

Meteoritics, vol. 28, no. 3, volume 28, page 376

Other

Allan Hills Far Western Icefield, Cosmogenic Nuclides, Terrestrial Ages

Scientific paper

The terrestrial age or residence time on the Earth's surface is an important parameter in determining the history of a meteorite. Terrestrial age can be determined using several radioisotopes, predominantly ^14C [1,2] and ^36Cl [3]. Terrestrial ^36Cl [3] and ^81Kr ages [4] established that the meteorites collected from the main ice field at Allan Hills were generally over 100,000 yr, beyond the range of ^14C dating. The old ages are generally thought to be due to burial and transport of meteorites in the ice. The observed age distribution gives some indication of the processes that have occurred. We have therefore undertaken a study of ^14C ages of meteorites from the other Allan Hills ice fields, where younger meteorites were expected from the few data previously available [3]. In this report, we concentrate on the Far Western ice field. Groups of meteorites from the other Allan Hills ice fields (Middle and Near Western) have also been studied. A suite of over 50 samples from the Far Western ice field was used in this study. The ^14C age distribution for meteorites at this site is shown in Fig. 1. Some achondrites from the Far Western ice field have also been studied and generally appear to be young in terrestrial age. The number of meteorites decreases with increasing age, with a possible small age offset of the maximum, indicating there might be some transport of meteorites through the ice. However, this transport cannot be for more than 5000-10,000 yr, and this indicates that the Far Western meteorites came from within a few kilometers of the site. Detailed AMLAMP sample location maps allowed us to plot ages as a function of location to indicate any dynamic effects. This map indicates little evidence for transport outside the area of several kilometers indicated from the total ^14C age distribution. These results will be compared to other locations in the vicinity and the effects of weathering will also be discussed. References: [1] Jull A. J. T. et al. (1989) GCA, 53, 2095. [2] Jull A. J. T. et al. (1993) Meteoritics, in press. [3] Nishiizumi K. et al. (1989) EPSL, 93, 299. [4] Freundel et al. (1986) GCA, 50, 2663. Fig. 1, which appears here in the hard copy, shows terrestrial ^14C ages for the Allan Hills Far Western ice field.

Affiliated with

Also associated with

No associations

Rating

14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica 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 14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and 14C Terrestrial Age Distribution of Meteorites from the Allan Hills Region, Antarctica will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1072949