Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 26 June 1998:
Vol. 280. no. 5372, pp. 2132 - 2139
DOI: 10.1126/science.280.5372.2132
Prev | Table of Contents

Technical Comments

Ambiguities in Direct Dating of Rock Surfaces Using Radiocarbon Measurements

W. Beck, D. J. Donahue, A. J. T. Jull, G. Burr W. S. Broecker G. Bonani, I. Hajdas E. Malotki

An attempt was made to date rock surfaces with accelerator mass spectrometry (AMS) radiocarbon measurements of rock varnishes or rock weathering rinds. In two case studies, samples pretreated in the laboratory of Dr. Ronald Dorn prior to AMS analysis have been found to contain significant quantities of carbon-rich materials of two distinct classes. Type I material resembles bituminous coal, whereas type II material resembles pyrolized wood charcoal fragments. In samples where these type I and type II materials were separated and AMS-radiocarbon dated, they were found to have widely differing radiocarbon ages. In these cases, the measurement of the radiocarbon age of the entire sample would yield results that are, at best, ambiguous. Neither type I nor type II materials were found in comparable samples that were independently prepared.

NSF AMS Facility, University of Arizona, Tucson, AZ 85721, USA
Lamont Doherty Earth Observatory, Columbia University,
Palisades, NY 10964, USA
Institut fuer Teilchenphysik, AMS Laboratory, ETH Hoenggerberg, CH-8093 Zurich, Switzerland.
Department of Modern Languages,
Northern Arizona University,
Flagstaff, AZ 86011, USA

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Diversity of Microorganisms within Rock Varnish in the Whipple Mountains, California.
K. R. Kuhlman, W. G. Fusco, M. T. La Duc, L. B. Allenbach, C. L. Ball, G. M. Kuhlman, R. C. Anderson, I. K. Erickson, T. Stuecker, J. Benardini, et al. (2006)
Appl. Envir. Microbiol. 72, 1708-1715
   Abstract »    Full Text »    PDF »
Desert pavements and associated rock varnish in the Mojave Desert: How old can they be?.
(2001)
Geology 29, 855-858
Methodology for using precarious rocks in Nevada to test seismic hazard models.
J. G. Anderson and J. N. Brune (1999)
Bulletin of the Seismological Society of America 89, 456-467
   Abstract »    PDF »
Ambiguities in Direct Dating of Rock Surfaces Using Radiocarbon Measurements.
W. Beck, D. J. Donahue, A. J. Jull, G. Burr, W. S. Broecker, G. Bonani, I. Hajdas, E. Malotki;, and R. I. Dorn; (1998)
Science 280, 2132-2139
   Full Text »


ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)