First successful 40Ar-39Ar dating of glauconies: Argon recoil in single grains of cryptocrystalline material

Research Article| January 01, 1993 First successful 40Ar-39Ar dating of glauconies: Argon recoil in single grains of cryptocrystalline material P. E. Smith; P. E. Smith 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada Search for other works by this author on: GSW Google Scholar N. M. Evensen; N. M. Evensen 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada Search for other works by this author on: GSW Google Scholar D. York D. York 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information P. E. Smith 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada N. M. Evensen 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada D. York 1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1993) 21 (1): 41–44. https://doi.org/10.1130/0091-7613(1993)021<0041:FSAADO>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation P. E. Smith, N. M. Evensen, D. York; First successful 40Ar-39Ar dating of glauconies: Argon recoil in single grains of cryptocrystalline material. Geology 1993;; 21 (1): 41–44. doi: https://doi.org/10.1130/0091-7613(1993)021<0041:FSAADO>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Potassium-argon dating of glaucony, one of the few widely occurring authigenic materials in the sedimentary record, has provided a large percentage of the dates used for the calibration of the geologic time scale. This material has been considered unsuitable for 40Ar-39Ar dating because of the large losses of neutron-induced 39Ar during or subsequent to irradiation of samples. We have measured recoiled 39Ar and 37Ar from single grains of glaucony (100-350 μm in diameter). Irradiations were done both in air and in vacuo by using a microampoule technique of encapsulation. The observed in vacuo behavior of recoiled atoms can be readily understood by a simple model of their interaction with the network of very fine laminae composing the grains. When the microampoule technique is used, the integrated 40Ar-39Ar ages and their associated precision compare very favorably with conventional K-Ar results. Because glauconies are inherently heterogeneous populations, owing to their complex evolution, it is anticipated that single-grain 40Ar-39Ar dating may lead to significant refinements in the geologic time scale, especially for the Cenozoic. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.