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  Radiocarbon, Volume 43, Number 2B (Proceedings of the 17th International Radiocarbon Conference, Part 2 of 3, 2001)

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Radiocarbon, Volume 43, Number 3 (Proceedings of the 17th International Radiocarbon Conference, Part 3 of 3, 2001)

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Radiocarbon, Volume 43, Number 1 (2001)

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Radiocarbon, Volume 43, Number 2A (Proceedings of the 17th International Radiocarbon Conference, Part 1 of 3, 2001)

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Thanks from Radiocarbon

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Renee Kra (1936-2001)

  Elliott, Kim (Department of Geosciences, The University of Arizona, 2001-01-01)
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  From the Guest Editor

  Carmi, Israel (Department of Geosciences, The University of Arizona, 2001-01-01)
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  From the Editor

  Jull, A. J. T. (Department of Geosciences, The University of Arizona, 2001-01-01)
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  Editorial Board

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Editorial Board

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Editorial Board

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Editorial Board

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Conference Participants

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Acknowledgments of Financial Support

  Department of Geosciences, The University of Arizona, 2001-01-01
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  A Special Dedication to Israel Carmi

  Boaretto, Elisabetta (Department of Geosciences, The University of Arizona, 2001-01-01)
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  2001 Price List

  Department of Geosciences, The University of Arizona, 2001-01-01
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  Transition Dating' – A Heuristic Mathematical Approach to the Collation of Radiocarbon Dates from Stratified Sequences

  Sharon, Ilan (Department of Geosciences, The University of Arizona, 2001-01-01)

  A heuristic approach, nicknamed "transition dating," was used to date sequences of early Iron Age contexts using a series of 14C determinations. The basic principles of transition dating are simple and intuitive: 1) attempt to date transitions between periods, phases, etc. Rather than the phases themselves, and 2) the most plausible date for that transition is one that is later than the dates from contexts preceding it, and is still earlier than the dates succeeding it. Hypotheses regarding the actual date of each transition may be evaluated using an appropriate loss function. These loss functions can also be adjusted or weighted by the user to account differentially for the various factors causing the distortion or "fuzz" in the dates.
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  Transport of Sellafield-Derived 14C from the Irish Sea Through the North Channel

  Gulliver, Pauline; Cook, Gordon T.; MacKenzie, Angus B.; Naysmith, Philip; Anderson, Robe (Department of Geosciences, The University of Arizona, 2001-01-01)

  Since the early 1950s, the Sellafield nuclear fuel reprocessing plant in Northwest England has released radiocarbon into the Irish Sea in a mainly inorganic form as part of its authorized liquid effluent discharge. In contrast to the trend in which the activities of most radionuclides in the Sellafield liquid effluent have decreased substantially, 14C discharges have increased since 1994–95. This has largely been due to a policy change favoring marine discharges over atmospheric discharges. 14C is radiologically important due to its long half life, mobility in the environment, and propensity for entering the food chain. Current models for radionuclide dispersal in the Irish Sea are based on a reversible equilibrium distribution coefficient (kd), an approach which has been shown to be inadequate for 14C. Development of predictive models for the fate of Sellafield-derived 14C requires a thorough understanding of the biogeochemical fluxes between different carbon reservoirs and the processes controlling the net flux of 14C out of the Irish Sea, through the North Channel. In this study, both an empirical and a halving time approach indicate that close to 100% of the 14C that is discharged from Sellafield is dispersed beyond the Irish Sea on a time-scale of months in the form of DIC, with little transfer to the PIC, POC, and DOC fractions, indicating that the “dilute and disperse” mechanism is operating satisfactorily. This is consistent with previous research that indicated little transfer of 14C to Irish Sea sediments. While significant 14C enhancements have been observed in the biota of the Irish Sea, this observation is not necessarily in conflict with either of the above as the total biomass has to be taken into account in any calculations of 14C retention within the Irish Sea.
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  The Varying Radiocarbon Activity of Some Recent Submerged Estonian Plants Grown in the Early 1990s

  Olsson, Ingrid U.; Kaup, Enn (Department of Geosciences, The University of Arizona, 2001-01-01)

  Eleven samples of aquatic plants from three Estonian lakes were analyzed for their radiocarbon content in a collaboration between the laboratories in Tallinn and Uppsala. delta-13C values for the actual species were compiled to allow normalization of activities measured in Tallinn without delta-13C values. The range for well determined species is usually a few per mil and the statistical uncertainty greater than or equal to 1 per mil delta-13C values vary considerably for different Potamogeton species and Myriophyllum spp. Lake Antu Sinijarv and Lake Päidre are hard-water lakes containing 300 and 200 mg HCO3-/L, respectively. One sample consisted of a carbonate crust deposited on a Ceratophyllum demersum plant in L. Antu Sinijarv. Its Delta-14C value was -147.3 +/6.7 per mil in 1990, whereas the plant had a value of -74.1 +/8.0 per mil (delta-13C = -35.0 per mil). The same species in L. Päidre had a Delta-14C value of +8.0 +/8.8 per mil (delta-13C = -25.2 per mil) in 1992. Other species in L. Päidre contained more 14C, from a Delta-14C value of about +30 per mil to about +155 per mil, the latter value measured in Tallinn on floating leaves of Nuphar lutea, close to that of the contemporaneous atmospheric CO2. In the third lake, Lake Punso, containing >30 mg HCO3-/L, the stems of Nuphar lutea exhibited in 1990 a memory effect: the activity, Delta-14C = 209.6 +/10.3 per mil, significantly exceeded that of the contemporaneous atmospheric CO2. However, the floating leaves of the same plant had the Delta-14C value 143.1 +/10.0 per mil, close to the atmospheric 14C level in 1990. The memory is explained by nutrients stored in the root stock, used when the growth starts.
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  Towards an AMS Radiocarbon Chronology of Predynastic Egyptian Ceramics

  Savage, Stephen H. (Department of Geosciences, The University of Arizona, 2001-01-01)

  The wide and varied connections between Israel and Egypt during the Early Bronze Age/Predynastic are frequently calibrated through ceramics that depend to a large degree on two seriation methods developed for Predynastic Egypt. Petrie’s seriation technique and Kaiser’s Stufe dating method utilize whole forms from mortuary contexts. Because of the ways they were developed and deployed in Predynastic research, a logical tautology exists that makes their usage highly problematic. Radiocarbon dating of the Predynastic is vital if we are to untangle existing ceramic chronologies. But up to now, almost all 14C dates have come from domestic contexts where whole vessels are not usually found and which differ significantly from cemeteries in their ceramic assemblages. A 14C-based chronology of whole forms in the Petrie Corpus is thus highly desirable, but has proven elusive until now. Samples of organic materials and Black-Topped Red Ware vessels from over 100 graves in the Predynastic Cemetery, N7000, at Naga-ed-Dêr have recently been submitted for dating with AMS methods, providing the first comprehensive 14C chronology of a Predynastic cemetery. The results are compared to a suite of recalibrated dates from Upper Egyptian Predynastic domestic contexts, which allows the 14C chronology for the region to be further refined. Absolute date ranges for a number of ceramic forms can be estimated for the first time, and results of early analysis are discussed.

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