scholarly journals Radiocarbon Dating of Anthropogenic Carbonates: What Is the Benchmark for Sample Selection?

Heritage ◽  
2020 ◽  
Vol 3 (4) ◽  
pp. 1416-1432
Author(s):  
Michael B. Toffolo
Keyword(s):  
Calcium Carbonate ◽  
Cultural Evolution ◽  
Atmospheric Carbon Dioxide ◽  
Radiocarbon Dating ◽  
Sample Selection ◽  
Hydrated Lime ◽  
Radiocarbon Dates ◽  
Synthetic Materials ◽  
Lime Plaster ◽  
Definition Of

Anthropogenic carbonates are pyrotechnological products composed of calcium carbonate, and include wood ash, lime plaster/mortar, and hydraulic mortar. These synthetic materials are among the first produced by humans, and greatly influenced their biological and cultural evolution. Therefore, they are an important component of the archeological record that can provide invaluable information about past lifeways. One major aspect that has been long investigated is the possibility of obtaining accurate radiocarbon dates from the pyrogenic calcium carbonate that makes up most of these materials. This is based on the fact that anthropogenic carbonates incorporate atmospheric carbon dioxide upon the carbonation of hydrated lime, and thus bear the radiocarbon signature of the atmosphere at a given point in time. Since plaster, mortar, and ash are highly heterogeneous materials comprising several carbon contaminants, and considering that calcium carbonate is prone to dissolution and recrystallization, accurate dating depends on the effectiveness of protocols aimed at removing contaminants and on the ability to correctly identify a mineral fraction that survived unaltered through time. This article reviews the formation and dissolution processes of pyrogenic calcium carbonate, and mineralogical approaches to the definition of a ‘dateable fraction’ based on its structural properties.

scholarly journals Preparation Techniques for Radiocarbon Dating of Potsherds

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 276-283 ◽  
Author(s):  
Jacques Evin ◽  
Martine Gabasio ◽  
Jean-Claude Lefevre
Keyword(s):  
Calcium Carbonate ◽  
Low Temperature ◽  
Radiocarbon Dating ◽  
Field Experiments ◽  
Radiocarbon Dates ◽  
Preparation Techniques

Origins of carbon in potsherds are studied through field experiments which involve firing pots containing selected components and laboratory analyses. As temper seems to be the main source of carbon, radiocarbon dates may be too old if calcium carbonate is used. We can avoid the carbon from the clay by low-temperature burning of samples.

scholarly journals Radiocarbon Dating for the Reconstruction of the 1717 CE Triolet Rock Avalanche in the Mont Blanc Massif, Italy

2021 ◽  
Vol 8 ◽  
Author(s):  
Irka Hajdas ◽  
Ursula Sojc ◽  
Susan Ivy-Ochs ◽  
Naki Akçar ◽  
Philip Deline
Keyword(s):  
Sample Preparation ◽  
Confidence Level ◽  
Radiocarbon Dating ◽  
Landscape Evolution ◽  
Sample Selection ◽  
Rock Avalanche ◽  
Time Frame ◽  
Peat Bog ◽  
Radiocarbon Dates ◽  
Mont Blanc Massif

The Arp Nouva peat bog located in the upper Ferret Valley in the Mont Blanc massif was critically evaluated since published radiocarbon dates have led to controversial conclusions on the formation of this swamp. Radiocarbon dating of woody fragments from three pits of up to 1 m depth was used to discuss the question of whether the historically documented rock avalanche occurring in 1717 CE overran the peat bog or settled prior to its formation. For the deepest samples in the pits, calibrated radiocarbon ages between 1,652 and 1950 CE (95.4%; confidence level) were obtained, which fit very well into the time frame of the historical documented 1717 CE rock avalanche event. It can, therefore, be concluded that the Arp Nouva peat bog was formed by blockage of the Bella Combe torrent by the rock avalanche deposits. Furthermore, careful sample preparation with consequent separation of woody fragments from the bulk peat sample has shown that the problem of too old 14C ages can be circumvented. This work demonstrates that a combined geomorphological and geochronological approach is the most reliable way to reconstruct landscape evolution. The key to successful 14C dating is careful sample selection and the identification of the material that might not be ideal for chronological reconstructions.

Synchronising radiocarbon dating and the Egyptian historical chronology by improved sample selection

Antiquity ◽  
2012 ◽  
Vol 86 (333) ◽  
pp. 868-883 ◽  
Author(s):  
M.W. Dee ◽  
J.M. Rowland ◽  
T.F.G. Higham ◽  
A.J. Shortland ◽  
F. Brock ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Sample Selection ◽  
Radiocarbon Dates

Egypt has some of the oldest written records and extended lists of named rulers. But radiocarbon dates have only fulfilled expectations 66 per cent of the time. So why haven&t the two types of dating made a better match? The authors provide a dozen excellent reasons, which will sound the alarm among researchers well beyond Dynastic Egypt.

Calibrated Radiocarbon Dating at Keatley Creek: The Chronology of Occupation at a Complex Hunter-Gatherer Village

2003 ◽  
Vol 68 (4) ◽  
pp. 719-735 ◽  
Author(s):  
William C. Prentiss ◽  
Michael Lenert ◽  
Thomas A. Foor ◽  
Nathan B. Goodale ◽  
Trinity Schlegel
Keyword(s):  
British Columbia ◽  
Radiocarbon Dating ◽  
Climatic Factors ◽  
Climatic Warming ◽  
Radiocarbon Dates ◽  
Population Aggregation ◽  
Selective Environment

This paper provides an analysis of radiocarbon dates acquired during earlier and recent field seasons at the Keatley Creek site, southern British Columbia. Results indicate that early occupations predating 1900 cal. B.P. occurred, but were not likely associated with population aggregation and large housepits. The aggregated village appears to have emerged by approximately 1700 cal. B.P. and was abandoned at approximately 800 cal. B.P. A break in the occupational sequence is recognized at 1450-1350 cal. B.P. and one other short break may have occurred shortly after 1250 cal. B.P. Peak socioeconomic complexity appears to have been achieved between 1350 and 800 cal B.P. Climatic warming may have provided a selective environment favoring population aggregation and intensification during this time. The final abandonment of the Keatley Creek village appears to have been part of a regional phenomenon suggesting the possibility that climatic factors were important in this case as well.

Sign in / Sign up

Export Citation Format

Share Document