• 1995 Price List

      Department of Geosciences, The University of Arizona, 1995-01-01
    • 7th International Conference on Accelerator Mass Spectrometry

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Associate Editors

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Calibration 1993

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Comparing Long-Term Atmospheric 14C and 3H Records near Groningen, the Netherlands with Fruholmen, Norway and Izaña, Canary Islands 14C Stations

      Meijer, Harro J. A.; van der Plicht, Johannes; Gislefoss, Jorunn S.; Nydal, Reidar (Department of Geosciences, The University of Arizona, 1995-01-01)
      We present the results of the 14CO2 atmospheric monitoring station at the Smilde observation station, near Groningen, the Netherlands, a typical continental station. We compared these data, for absolute values and annual variation, with data from Fruholmen, Nordkapp, Norway and Izaña, Tenerife, Canary Islands, which are situated in areas less influenced by fossil-fuel CO2. The 20-yr Smilde record shows much seasonal variation (peak-to-trough variation is approximately 30 per mil in contrast to approximately 12 per mil for Fruholmen, and approximately 5 per mil for Izaña) and a lower overall value due to fossil-fuel consumption, in accordance with findings from similar stations in continental Western Europe. The Fruholmen and Izaña data show fairly equal mean Delta-14C levels, but differ in seasonal amplitude. This difference could be due partly to the elevation difference between the stations. The Izaña station also has a slow exchange with the ground-level air because of an inversion layer. It is speculative whether annual injection of 14C from the stratosphere also plays a role. We give the Groningen long record of tritium in precipitation, showing profound seasonality.
    • Dating of Lake and Loess Sediments

      Beer, Juerg; Sturm, Michael (Department of Geosciences, The University of Arizona, 1995-01-01)
      Lake and loess sediments represent archives that record important information about the local, regional and global climate conditions in the past. Lake sediments consist of autochthonous particles formed by biogeochemical processes within the lake and allochthonous particles brought into the lake from the catchment area. After deposition, the stratigraphy of the sediment can be altered by chemical, physical and biological processes. Under favored conditions, the sediment shows individual annual layers (varves), which can be used to date the sediment. Other dating methods are based on radioactive decay (14C, 210Pb) or on time markers such as tephra layers, deposits of natural catastrophes, e.g., floods, or radioactivity, e.g., emissions from a nuclear power plant.
    • Friends of Radiocarbon

      Department of Geosciences, The University of Arizona, 1995-01-01
    • From the Editor

      Long, Austin (Department of Geosciences, The University of Arizona, 1995-01-01)
    • Intercomparison of High-Precision 14C Measurements at the University of Arizona and the Queen's University of Belfast Radiocarbon Laboratories

      Kalin, R. M.; McCormac, F. G.; Damon, P. E.; Eastoe, C. J.; Long, Austin (Department of Geosciences, The University of Arizona, 1995-01-01)
      High-precision measurements were completed concurrently at the University of Arizona and the Queen's University of Belfast on blind samples of Irish oak originally measured for the 1986 radiocarbon calibration curve. Subsequent single-year Sequoiadendron results were decadally averaged and compared with published results on decadal Douglas-fir samples. The results of these intercomparisons show that the Arizona high-precision results compare favorably with published values from the University of Washington, but show a systematic offset with published Belfast data.
    • Late Quaternary Chronology and Paleoclimates of the Eastern Mediterranean [Announcement]

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Liquid Scintillation Spectrometry 1992

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Mammoth Extinction: Two Continents and Wrangel Island

      Martin, Paul S.; Stuart, Anthony J. (Department of Geosciences, The University of Arizona, 1995-01-01)
    • Problems in the Extension of the Radiocarbon Calibration Curve (10-13 Kyr BP)

      Hajdas, Irena; Ivy-Ochs, S. D.; Bonani, Georges (Department of Geosciences, The University of Arizona, 1995-01-01)
      Radiocarbon dating of varved lake sediments shows that, during the Late Glacial (10-12 kyr BP), the offset between the 14C and the absolute time scales was ca. 1 kyr. Varve counting and accelerator mass spectrometry (AMS) dating were used to build absolute and 14C time scales of sediments from two lakes-—Soppensee, Switzerland and Holzmaar, Germany. The resulting chronologies extend back to ca. 12.9 kyr cal BP (12.1 kyr BP) in the case of Soppensee and to ca. 13.8 kyr cal BP (12.6 kyr BP) in the Holzmaar record. They compare well with each other but differ significantly from the 14C-U/Th chronology of corals (Bard et al.1993; Edwards et al.1993).
    • Radiocarbon Dating Evidence for Mammoths on Wrangel Island, Arctic Ocean, Until 2000 BC

      Vartanyan, S. L.; Arslanov, Kh A.; Tertychnaya, T. V.; Chernov, S. B. (Department of Geosciences, The University of Arizona, 1995-01-01)
      Radiocarbon dating results of mammoth tusks, teeth and bones collected on Wrangel Island between 1989 and 1991 reveal a unique mammoth refugium during the Holocene. We used an improved chemical procedure to obtain and purify collagen from bone. Benzene synthesized from the samples was measured using a liquid scintillation counter. The validity of our data has been confirmed by the results of our measurements on two international control sample series (IAEA and TIRI) and by parallel measurements of Wrangel Island mammoth remains at other laboratories.
    • Radiocarbon Dating of Scrolls and Linen Fragments from the Judean Desert

      Jull, Timothy A. J. T.; Donahue, Douglas J.; Broshi, Magen; Tov, Emanuel (Department of Geosciences, The University of Arizona, 1995-01-01)
      We report on new 14C measurements of samples of 18 texts (scrolls) and 2 linen fragments from Qumran Caves 1, 2, and 4 and from Naḥal Ḥever, both in the Dead Sea region. The radiocarbon results are in good agreement with estimates of age based on paleography.
    • Radiocarbon Dating the Holocene in the Gościąż Lake Floating Varve Chronology

      Hajdas, Irena; Bonani, Georges; Goślar, Tomasz (Department of Geosciences, The University of Arizona, 1995-01-01)
      Terrestrial macrofossils selected from laminated sediment of Lake Gościąż were dated by AMS. Thus, part of the floating varve chronology (FVC) (Goślar et al. 1993) between radiocarbon ages of 4225 +/45 and 7740 +/85 BP can be compared and placed on the 14C calibration curve. As a result of our dating, the top of the FVC is now dated between 3120 and 3300 cal BF, i.e., 3210 +/90 cal BP.
    • Radiocarbon, Volume 37, Number 1 (1995)

      Department of Geosciences, The University of Arizona, 1995-01-01
    • Robert Stuckenrath, 1927-1994

      Adovasio, J. M. (Department of Geosciences, The University of Arizona, 1995-01-01)
    • Storage Conditions and Physical Treatments Relating to the Dating of the Dead Sea Scrolls

      Caldararo, Niccolo (Department of Geosciences, The University of Arizona, 1995-01-01)
      The Dead Sea Scrolls have been analyzed by paleographic, non-destructive and destructive testing. The dates of their creation have been in dispute since their discovery. Research has established their authenticity, but a variety of conditions including the methods of skin preparation, variation in storage conditions and post-discovery restoration treatments could have introduced changes now affecting dating efforts. Comprehensive analyses were not possible until recently. Such analysis must be performed to establish a concrete framework for all the texts.
    • The 14C Age of the Icelandic Vedde Ash: Implications for Younger Dryas Marine Reservoir Age Corrections

      Austin, W. E. N.; Bard, Edouard; Hunt, J. B.; Kroon, Dick; Peacock, J. D. (Department of Geosciences, The University of Arizona, 1995-01-01)
      Increased marine 14C reservoir ages from the surface water of the North Atlantic are documented for the Younger Dryas period. We use terrestrial and marine AMS 14C dates from the time of deposition of the Icelandic Vedde Ash to examine the marine 14C reservoir age. This changed from its modem North Atlantic value of ca. 400 yr to ca. 700 yr during the Younger Dryas climatic event. The increased marine reservoir age has implications for both comparing climatic time series dated by 14C and understanding palaeoceanographic changes that generated the increase.