Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-23T21:03:51.329Z Has data issue: false hasContentIssue false

How Smooth Should Curves Be for Calibrating Radiocarbon Ages?

Published online by Cambridge University Press:  18 July 2016

Torbjörn E. Törnqvist
Affiliation:
Department of Physical Geography, Utrecht University, P.O. Box 80115, NL-3508 TC Utrecht The Netherlands
Marc F. P. Bierkens
Affiliation:
Department of Physical Geography, Utrecht University, P.O. Box 80115, NL-3508 TC Utrecht The Netherlands
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We show that smoothed versions of the high-resolution calibration curve should be used when 14C ages are calibrated with large (> ∼30 14C yr) measurement errors (represented by standard deviation δm) or are mixtures of elements of variable age (natural sample error with standard deviation δn). The degree of smoothing should agree with the standard deviation of total sample error, δt, the square root of the quadratic sum of δm and δn. However, in most cases, δt is not well known, especially due to difficulties in quantifying δn. We present an inverse method that gives a measure of mean δt, for different materials that are widely used in (conventional) 14C dating. Calculations with large (>100) data sets of wood, charcoal, ombrotrophic peat and minerotrophic peat/gyttja samples indicate that δt of such materials is generally much larger than previously assumed, mainly because of large values of δn. This means that particularly in organic deposits, strongly smoothed calibration curves should be used where medium-term 14C variations (wiggles) are completely straightened. This has especially major consequences for calibrating 14C histograms for natural 14C variations. We conclude that 14C histograms consisting of samples of organic deposits do not require correction for medium-term 14C variations and that uncalibrated 14C histograms need not be as suspect as is usually believed.

Type
Articles
Copyright
Copyright © The American Journal of Science 

References

Aitchison, T. C., Leese, M., Michczynska, D. J., Mook, W. G., Otlet, R. L., Ottaway, B. S., Pazdur, M. F., van der Plicht, J., Reimer, P. J., Robinson, S. W., Scott, E. M., Stuiver, M. and Weninger, B. 1989 A comparison of methods used for the calibration of radiocarbon dates. in Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 846862.CrossRefGoogle Scholar
Berendsen, H. J. A. 1982 De genese van het landschap in het zuiden van de provincie Utrecht, een fysisch-geografische studie. Utrechtse Geografische Studies 25: 1255.Google Scholar
Casparie, W. A. 1972 Bog Development in Southeastern Drenthe (The Netherlands). The Hague, W. Junk: 271 P.Google Scholar
de Jong, A. F. M. and Mook, W. G. 1981 Natural C-14 variations and consequences for sea-level fluctuations and frequency analysis of periods of peat growth. in van Loon, A. J., ed., Quaternary Geology: A Farewell to A. J. Wiggers. Geologie en Mijnbouw 60: 331336.Google Scholar
Dupont, L. M. 1986 Temperature and rainfall variation in the Holocene based on comparative palaeoecology and isotope geology of a hummock and a hollow (Bourtangerveen, The Netherlands). Review of Palaeobotany and Palynology 48: 71159.CrossRefGoogle Scholar
Dupont, L. M. and Brenninkmeijer, C. A. M. 1984 Palaeobotanic and isotopic analysis of late Subboreal and early Subatlantic peat from Engbertsdijksveen VII, The Netherlands. Review of Palaeobotany and Palynology 41: 241271.CrossRefGoogle Scholar
Geyh, M. A. 1971 Middle and young Holocene sea-level changes as global contemporary events. Geologiska Föreningens i Stockholm Förhandlingar 93: 679692.CrossRefGoogle Scholar
Geyh, M. A. 1980 Holocene sea-level history: Case study of the statistical evaluation of 14C dates. in Stuiver, M. and Kra, R. S., eds., Proceedings of the 10th International 14C Conference. Radiocarbon 22(3): 695704.CrossRefGoogle Scholar
International Study Group 1982 An inter-laboratory comparison of radiocarbon measurements in tree rings. Nature 298: 619623.CrossRefGoogle Scholar
Janssen, C. R. and ten Hove, H. A. 1971 Some Late Holocene pollen diagrams from the Peel raised bogs (southern Netherlands). Review of Palaeobotany and Palynology 11: 753.CrossRefGoogle Scholar
Kuhry, P. 1985 Transgression of a raised bog across a coversand ridge originally covered with an oak-lime forest. Palaeoecological study of a Middle Holocene local vegetational succession in the Amtsven (northwest Germany). Review of Palaeobotany and Palynology 44: 303353.CrossRefGoogle Scholar
Lanting, J. N. and Mook, W. G. 1977 The Pre- and Protohistory of the Netherlands in Terms of Radiocarbon Dates. Groningen: 247 P.Google Scholar
Michczyńska, D. J., Pazdur, M. F. and Walanus, A. 1990 Bayesian approach to probabilistic calibration of radiocarbon ages. in Mook, W. G. and Waterbolk, H. T., eds., Proceedings of the 2nd International Symposium 14C and Archaeology. Strasbourg, PACT 29: 6979.Google Scholar
Middeldorp, A. A. 1982 Pollen concentration as a basis for indirect dating and quantifying net organic and fungal production in a peat bog ecosystem. Review of Palaeobotany and Palynology 37: 225282.CrossRefGoogle Scholar
Middeldorp, A. A. 1986 Functional palaeoecology of the Hahnenmoor raised bog ecosystem - A study of vegetation history, production and decomposition by means of pollen density dating. Review of Palaeobotany and Palynology 49: 173.CrossRefGoogle Scholar
Mook, W. G. 1983 14C calibration curves depending on sample time-width. in Mook, W. G. and Waterbolk, H. T., eds. Proceedings of the International Symposium 14C and Archaeology. Strasbourg, PACT 8: 517525.Google Scholar
Mook, W. G., de Jong, A. F. M. and Geertsema, H. 1979 Archaeological implications of natural carbon-14 variations. Palaeohistoria 21: 918 Google Scholar
Mook, W. G. and Streurman, H. J. 1983 Physical and chemical aspects of radiocarbon dating. in Mook, W. G. and Waterbolk, H. T., eds. Proceedings of the International Symposium 14C and Archaeology. Strasbourg, PACT 8: 3155.Google Scholar
Pearson, G. W., Pilcher, J. R., Baillie, M. G. L., Corbett, D. M. and Qua, F. 1986 High-precision 14C measurement of Irish oaks to show the natural 14C variations from AD 1840 to 5210 BC. in Stuiver, M. and Kra, R. S., eds., Proceedings of the 12th International 14C Conference. Radiocarbon 28(2B): 911934.CrossRefGoogle Scholar
Pearson, G. W. and Stuiver, M. 1986 High-precision calibration of the radiocarbon time scale, 500-2500 BC. in Stuiver, M. and Kra, R. S., eds., Proceedings of the 12th International 14C Conference. Radiocarbon 28(2B): 839862.CrossRefGoogle Scholar
Scott, E. M., Aitchison, T. C., Harkness, D. D., Cook, G. T. and Baxter, M. S. 1990 An overview of all three stages of the International Radiocarbon Intercomparison. in Scott, E. M., Long, A. and Kra, R. S., eds., Proceedings of the International Workshop on Intercomparison of 14C Laboratories. Radiocarbon 32(3): 309319.CrossRefGoogle Scholar
Stolk, A., Hogervorst, K. and Berendsen, H. 1989 Correcting 14C histograms for the non-linearity of the radiocarbon time scale. Radiocarbon 31(2): 169177.CrossRefGoogle Scholar
Stolk, A., Törnqvist, T. E., Hekhuis, K. P. V., Berendsen, H. J. A. and van der Plicht, J. 1994 Calibration of 14C histograms: A comparison of methods. Radiocarbon 36(1): 110.CrossRefGoogle Scholar
Stuiver, M. and Pearson, G. W. 1986 High-precision calibration of the radiocarbon time scale, AD 1950-500 BC. in Stuiver, M. and Kra, R. S., eds., Proceedings of the 12th International 14C Conference. Radiocarbon 28(2B): 805838.CrossRefGoogle Scholar
Stuiver, M. and Reimer, P. 1989 Histograms obtained from computerized radiocarbon age calibration. in Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 817823.CrossRefGoogle Scholar
Törnqvist, T. E. and van Dijk, G. J. 1993 Optimizing sampling strategy for radiocarbon dating of Holocene fluvial systems in a vertically aggrading setting. Boreas 22: 129145.CrossRefGoogle Scholar
Törnqvist, T. E., de Jong, A. F. M., Oosterbaan, W. A. and van der Borg, K. 1992 Accurate dating of organic deposits by AMS 14C measurement of macrofossils. in Long, A. and Kra, R. S., eds., Proceedings of the 14th International 14C Conference. Radiocarbon 34(3): 566577.CrossRefGoogle Scholar
van der Plicht, J. 1993 The Groningen radiocarbon calibration program. in Stuiver, M., Long, A. and Kra, R. S., eds., Calibration 1993. Radiocarbon 35(1): 231237.Google Scholar
van der Plicht, J. and Mook, W. G. 1989 Calibration of radiocarbon ages by computer. in Long, A., Kra, R. S. and Srdoč, D., eds., Proceedings of the 13th International 14C Conference. Radiocarbon 31(3): 805816.CrossRefGoogle Scholar
van der Woude, J. D. 1983 Holocene paleoenvironmental evolution of a perimarine fluviatile area. Geology and paleobotany of the area surrounding the archeological excavation at the Hazendonk river dune (Western Netherlands). Analecta Praehistorica Leidensia 16: 1124.Google Scholar
van Dijk, G. J., Berendsen, H. J. A. and Roeleveld, W. 1991 Holocene water level development in The Netherlands’ river area; implications for sea-level reconstruction. Geologie en Mijnbouw 70: 311326.Google Scholar
van Geel, B. 1972 Palynology of a section from the raised peat bog “Wietmarscher Moor”, with special reference to fungal remains. Acta Botanica Neerlandica 21: 261284.CrossRefGoogle Scholar
van Geel, B. 1978 A palaeoecological study of Holocene peat bog sections in Germany and The Netherlands, based on the analysis of pollen, spores and macro- and microscopic remains of fungi, algae, cormophytes and animals. Review of Palaeobotany and Palynology 25: 1120.CrossRefGoogle Scholar
van Geel, B. and Mook, W. G. 1989 High-resolution 14C dating of organic deposits using natural atmospheric 14C variations. Radiocarbon 31(2): 151155.CrossRefGoogle Scholar
Witte, H. J. L. and van Geel, B. 1985 Vegetational and environmental succession and net organic production between 4500 and 800 B.P. reconstructed from a peat deposit in the western Dutch coastal area (Assendelver Polder). Review of Palaeobotany and Palynology 45: 239300.CrossRefGoogle Scholar