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The ice-free corridor: biogeographical highway or environmental cul-de-sac /Arnold, Thomas G. January 2006 (has links)
Thesis (Ph.D.) - Simon Fraser University, 2006. / Theses (Dept. of Archaeology) / Simon Fraser University. Includes bibliographical references (leaves 236-263). Also issued in digital format and available on the World Wide Web.
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Intracavity optogalvanic spectroscopy for radiocarbon analysis with attomole sensitivityIlkmen, Erhan, January 2009 (has links)
Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Applied Physics." Includes bibliographical references (p. 88-93).
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Accelerator mass spectrometry for radiocarbon dating : advances in theory and practiceBronk, Christopher Ramsey January 1987 (has links)
Accelerator mass spectrometry (AMS) has been used routinely for radiocarbon measurements for several years. During this period it has become evident neither the accuracy nor the range of the technique were as great as had originally been hoped. This thesis describes both theoretical work to understand the reasons for this and practical solutions to overcome some of the problems. The production and transport of the ions used in the measurements are found to be the most crucial stages in the process. The theories behind ion production by sputtering are discussed and applied to the specific case of carbon sputtered by caesium. Experimental evidence is also examined in relation to the theories. The phenomena of space charge and lens aberrations are discussed along with the interaction between ion beams and gas molecules in the vacuum. Computer programs for calculating phase space transformations are then described; these are designed to help investigations of the effects of space charge and aberrations on AMS measurements. Calculations using these programs are discussed in relation both to measured ion beam profiles in phase space and to the current dependent transmission of ions through the Oxford radiocarbon accelerator. Improvements have been made to this accelerator and these are discussed in the context of the calculations. There are many reasons for wishing to produce C<sup>-</sup> ions directly from carbon dioxide. The most suitable type of source for achieving this is the Middleton High Intensity Sputter Source. Experiments to evaluate the performance of such a source are described and detailed design criteria established. An ion source designed and built specifically for radiocarbon measurements using carbon dioxide is described. Experiments to evaluate its performance and investigate the underlying physical processes are discussed. The source is found to have a high efficiency enabling small samples (<100 μg of carbon) to be measured. The cross contamination is measured to be low (<0.1%) and the background currents are small; the implications of these results are discussed.
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The hydrochemistry and age of the water in the Milk River aquifer, Alberta, CanadaSwanick, Gerald Bernard. January 1982 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1982. / Includes bibliographical references (leaves 100-103).
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Natural ¹⁴C variationsJong, Adrianus Franciscus Maria de. January 1900 (has links)
Thesis (doctoral)--Rijksuniversiteit te Groningen, 1981. / "Stellingen" (2 p.) inserted. Includes bibliographical references (p. 103-114).
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Contemporary sediment dynamics and Holocene evolution of Hamford Water, Essex, EnglandRampling, Paul January 2000 (has links)
Contemporary sediment transport, suspended sediment flux, rates of intertidal sedimentation, and Holocene sedimentation history are assessed for Hamford Water, a small meso-tidal inlet and saltmarsh embayment in Essex, UK. Sediment transport rates are calculated using semi-empirical equations; suspended sediment flux is computed by integration of suspended sediment concentration and velocity across the inlet throat; intertidal sedimentation rates are assessed from monitoring of discrete markers on saltmarsh and mudflat; and Holocene sedimentation is estimated from radiocarbon dating of buried organic layers, sampled using a vibrocorer. Results show a tidal regime typical of ebb-dominated inlets: moderate, ebb-dominant flow (==1 m S·l) in the central ebb channel is matched by similar flood-dominant marginal channel flows. The sediment dynamics are not influenced by any fluvial input; there is negligible fresh water input. The net direction of sediment transport is predominantly ebb-orientated. Coarse sand transport pathways are circulatory and dependent on longshore drift. Sand (D = 0.25 mm) enters at the margins and is expelled in the central ebb channel. Negligible sand is transported further landward than the mouth; intertidal sedimentation relies mainly on levels of suspended sediment. Rates of intertidal sedimentation are spatially variable: tidal creek sedimentation is greater than saltmarsh, with a mean rate of 4.2mm yr"l. Buried organic horizons. radiocarbon dated to 600 years BP, are attributed to reclaimed land levels. Holocene sedimentation rates since 4300 years BP, estimated from 14C dating of shell bands. accord with current estimates of sea-level rise of approximately 1 mm i 1 • The role and evolution of the inlet entrance and ebb tidal delta are seen as critical to the evolution of the embayment as a whole. The interaction of the embayment with the adjacent coastal zone considered essential when fonnulating shoreline management plans. Hamford Water is considered an integral part of the Stour/OrwelllNaze coastal system.
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Ion beams for radiocarbon dating : the production, transport and measurement of C ̄beams for high energy mass spectrometryWhite, Nicholas Robin January 1981 (has links)
No description available.
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Characterization and radiocarbon dating of archaeological resins from southeast Asia.Lampert, C.D., Glover, I.C., Heron, Carl P., Stern, Ben, Shoocongdej, R., Thompson, Gill B. 2009 October 1919 (has links)
No / First presented at an August 2001 national meeting of the American Chemical Society, material in this book provides a cross-section of current research in the area of chemistry applied to archaeological questions. Examples are given of the use of analytical methods in the study of a variety of archaeological materials, and inferences that can be made based on data patterns are discussed. Emphasis is on nondestructive testing and new developments in determining an object's age and composition.
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Sediment transfer and storage in headwater basins of the Oregon Coast Range : transit times from ¹⁴C dated deposits /Underwood, Emily F. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 43-46). Also available on the World Wide Web.
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High-precision radiocarbon dating of political collapse and dynastic origins at the Maya site of Ceibal, GuatemalaInomata, Takeshi, Triadan, Daniela, MacLellan, Jessica, Burham, Melissa, Aoyama, Kazuo, Palomo, Juan Manuel, Yonenobu, Hitoshi, Pinzón, Flory, Nasu, Hiroo 07 February 2017 (has links)
The lowland Maya site of Ceibal, Guatemala, had a long history of occupation, spanning from the Middle Preclassic Period through the Terminal Classic (1000 BC to AD 950). The Ceibal-Petexbatun Archaeological Project has been conducting archaeological investigations at this site since 2005 and has obtained 154 radiocarbon dates, which represent the largest collection of radiocarbon assays from a single Maya site. The Bayesian analysis of these dates, combined with a detailed study of ceramics, allowed us to develop a high-precision chronology for Ceibal. Through this chronology, we traced the trajectories of the Preclassic collapse around AD 150–300 and the Classic collapse around AD 800–950, revealing similar patterns in the two cases. Social instability started with the intensification of warfare around 75 BC and AD 735, respectively, followed by the fall of multiple centers across the Maya lowlands around AD 150 and 810. The population of Ceibal persisted for some time in both cases, but the center eventually experienced major decline around AD 300 and 900. Despite these similarities in their diachronic trajectories, the outcomes of these collapses were different, with the former associated with the development of dynasties centered on divine rulership and the latter leading to their downfalls. The Ceibal dynasty emerged during the period of low population after the Preclassic collapse, suggesting that this dynasty was placed under the influence from, or by the direct intervention of, an external power.
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