• Radiocarbon and 11-Year Variations of Cosmic Rays

      Burchuladze, A. A.; Pagava, S. V.; Togonidze, G. I.; Avtandilashvili, M. V. (Department of Geosciences, The University of Arizona, 1993-01-01)
    • An Improved Method for Radiocarbon Dating Fossil Bones

      Arslanov, Kh A.; Svezhentsev, Yu S. (Department of Geosciences, The University of Arizona, 1993-01-01)
      We demonstrate here that the use of either the acid-alkali or Longin method alone does not fully extract contaminants from bone-collagen fractions. We present our methods and results of extracting bone collagen that involve successive use of both of these methods.
    • 15th International Radiocarbon Conference

      Department of Geosciences, The University of Arizona, 1993-01-01
    • Radiocarbon Dating Organic Detritus: Implications for Studying Ice Sheet Dynamics

      Punning, Jaan-Mati; Rajamäe, Raivo (Department of Geosciences, The University of Arizona, 1993-01-01)
      We present here a description of the 14C dating method used at the Institute of Geology, Estonian Academy of Science. We discuss results of geochronological studies of several stratigraphic sections, from which we estimate the age of the Late Weichselian (Late Valdaian) glacial maximum. 14C and paleobotanical data indicate that biodetrital materials comprise organic debris from various sources and suggest only a maximum age of investigated strata (16,000 BP).
    • Geochronology of Late Quaternary Events in Northeastern Russia

      Lozhkin, A. V. (Department of Geosciences, The University of Arizona, 1993-01-01)
      Radiocarbon-dated paleobotanical and palynological samples record complex changes of vegetation and climate in northeastern Russia during the Late Pleistocene and Holocene. Since the Kargin Interval (middle Wisconsin equivalent), which started 50 ka ago, we can distinguish two periods that were colder than the present. The Kirgilyakh was the earliest Karginsk cool period, dating to 45–39 ka BP. The second significant cool period dates to 33–30 ka BP. The boundary between the Kargin Interval and the last Late Pleistocene glaciation (Sartan, late Wisconsin equivalent) dates from 27 ka BP. The sharp change from herbaceous mossy tundra (Sartan) to light-coniferous larch forests (Holocene) in northeastern Russia dates to 12.5 ka ago. The Holocene thermal maximum, linked to the expansion of woody plants into the modern barren-ground tundra, dates from 9.5–8 ka BP.
    • Dynamics of Radiocarbon in Soils

      Cherkinsky, A. E.; Brovkin, V. A. (Department of Geosciences, The University of Arizona, 1993-01-01)
      We present here a model of humus accumulation in recent soils. We have estimated the coefficients of mineralization of humus and humic acid for a typical Chemozem soil. We suggest a technique for calculating the renewal time of soil with specific activity higher than the modem standard and discuss the results for different soils.
    • Geochronology of the Pleistocene and Holocene in the Fore-Urals

      Latypova, E. K.; Yakheemovich, B. L. (Department of Geosciences, The University of Arizona, 1993-01-01)
      The paper presents the results for the 14C dating obtained recently in the Laboratory of the Institute of Geology, Ufa Science Centre, Russian Academy of Science, on the basis of megafaunal bones, peats, wood and mollusk shells. Dates are reported in stratigraphic sequence from the Late Wurmian to the Holocene.
    • Geochronology of the Nival-Glacial Deposits of the Ukrainian Carpathian Mountains

      Kovalyukh, N. N.; Petrenko, L. V.; Kovalenko, V. V. (Department of Geosciences, The University of Arizona, 1993-01-01)
    • Radiocarbon Updates

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

      Department of Geosciences, The University of Arizona, 1993-01-01
    • The Reliability of Radiocarbon Dating Buried Soils

      Orlova, L. A.; Panychev, V. A. (Department of Geosciences, The University of Arizona, 1993-01-01)
      Variable 14C ages of paleosol organic matter (OM) cause difficulties in interpreting 14C data. We attempt to determine the reliability of OM 14C dates by examining different carbon-containing materials from soil horizons and paleosol fractions.
    • From the Editors

      Long, Austin; Punning, Jaan-Mati (Department of Geosciences, The University of Arizona, 1993-01-01)
    • LSC 92

      Department of Geosciences, The University of Arizona, 1993-01-01
    • Radiocarbon, Volume 35, Number 3 (1993)

      Department of Geosciences, The University of Arizona, 1993-01-01
    • Late Quaternary Chronology and Paleoclimates of the Eastern Mediterranean

      Department of Geosciences, The University of Arizona, 1993-01-01
    • Geochronology of the Holocene of the Belorussian Polessie

      Matveev, A. V.; Krutous, E. A.; Zernitskaya, V. P. (Department of Geosciences, The University of Arizona, 1993-01-01)
      We distinguished major stages of the last glaciation (Bulling, Older Dryas, Allerod, Younger Dryas) and the Holocene by radiocarbon dating and paleobotanical analyses. Our paleobotanical investigation of peatlands is well correlated with independent 14C data. We establish that the Atlantic and Subboreal stages of the Holocene have three divisions, and that the Subatlantic has two.
    • Laboratories

      Department of Geosciences, The University of Arizona, 1993-01-01
    • Radiocarbon Dating and Tephrochronology in Kamchatka

      Braitseva, O. A.; Sulerzhitsky, L. D.; Litasova, S. N.; Melekestsev, I. V.; Ponomareva, V. V. (Department of Geosciences, The University of Arizona, 1993-01-01)
      We discuss results of 14C dates obtained from areas of young volcanoes in Kamchatka. We apply these dates to reconstructing regional volcanic activity during the Holocene.
    • Radiocarbon Chronology of Archaeological Sites of the Kurile Islands

      Zaitseva, G. I.; Popov, S. G.; Krylov, A. P.; Knorozov, Yu V.; Spevakovskiy, A. B. (Department of Geosciences, The University of Arizona, 1993-01-01)
    • Radiocarbon Chronology of Early Medieval Archaeological Sites in Northwestern Russia

      Popov, S. G.; Svezhentsev, Yu S.; Zaitseva, G. I. (Department of Geosciences, The University of Arizona, 1993-01-01)
      A reliable archaelogical chronology for medieval sites in northwestern Russia depends in part on a refined regional calibration scale for 14C dates. We present results of dates on tree-ring series from Novgorod that show a systematic discrepancy from European calibration curves, and that underline the need for more extensive 14C dating as the basis of an extended calibration curve for the region.