These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The Edge of Time: Dating Young Volcanic Ash Layers with the 40Ar-39Ar Laser Probe.
    Author: Chen Y, Smith PE, Evensen NM, York D, Lajoie KR.
    Journal: Science; 1996 Nov 15; 274(5290):1176-8. PubMed ID: 8895463.
    Abstract:
    Argon-40-argon-39 single-crystal dating of young (5000 to 30,000 years ago) volcanic ash layers erupted from the Mono Craters, California, shows that the method can yield meaningful ages in Holocene tephra. Because of ubiquitous xenocrystic contamination, the data do not form isochrons but plot in wedge-shaped regions on an argon isotopic diagram. The upper boundary of the region is an isochron matching the 14C-derived age of the eruption. Such contamination-related patterns may be common in dating young materials by the single-crystal method. Argon dating by this method can help refine the time scale of physical and biological evolution over the past 100,000 years.
    [Abstract] [Full Text] [Related] [New Search]