AMS ¹⁴C Dating at the Scottish Universities Environmental Research Centre (SUERC) Radiocarbon Dating Laboratory

Abstract

ABSTRACT. This paper describes all the major procedures adopted by the Scottish Universities Environmental Research Centre (SUERC) Radiocarbon Dating Laboratory. This includes sample pretreatment, graphite production, accelerator mass spectrometry (AMS) measurement, associated stable isotope measurements, data handling, and age calculations, but with the main emphasis being on the chemical pretreatment methods. All of the above enable the laboratory to provide a complete analytical service comprising advice on sample selection, preparation and analysis of samples, and Bayesian analysis of resulting 14 C (and other) data. This applies to both our research and commercial activities. The pretreatment methods that we mainly focus on are used to remove contaminant carbon from a range of sample types or to isolate a particular chemical fraction from a sample prior to combustion/ hydrolysis, graphitization, and subsequent AMS 14 C measurement. The methods described are for bone (collagen extraction, with and without ultrafiltration), cremated bone, tooth enamel, charcoal, grain, carbon residues, shell, wood (including alpha-cellulose isolation), peat, sediments, textiles, fuel/biofuel, and forensic samples.

Cremation Practices and the Creation of Monument Complexes: The Neolithic Cremation Cemetery at Forteviot, Strathearn, Perth & Kinross, Scotland, and its comparanda

“…The samples were all single entities (Ashmore 1999), of short-life material, either charcoal or cremated human bone. The samples were processed for radiocarbon dating at the Scottish Universities Environmental Research Centre, East Kilbride (SUERC) following the methods described by Dunbar et al (2016). The graphite was then pressed into aluminium target holders for subsequent AMS analysis (Xu et al 2004;Naysmith et al 2010).…”

Interwoven Strands for Refining the Chronology of the Neolithic Tell of Vinča-Belo Brdo, Serbia

“…All are conventional radiocarbon ages, corrected for fractionation (Stuiver and Polach 1977). The samples dated by the Scottish Universities Environmental Research Centre (SUERC-) were pretreated, combusted, and dated by Accelerator Mass Spectrometry (AMS) as described by Dunbar et al (2016). The animal bone samples were processed by gelatinisation and ultrafiltration.…”

Investigation of the Analytical F14C Bone Background Value at SUERC

“…The alpha cellulose is prepared using a modification of the technique of Hoper et al (1998) as described in Dunbar et al (2016). This wood was used in the VIRI study (Sample K), and has a consensus value of 0.0576 ± 0.0062 pMC (F 14 C= 0.0006 ± 0.0001) (Scott et al 2007(Scott et al , 2010a(Scott et al , 2010b.…”

“…At this point, the collagen solution is transferred to pre-cleaned Vivaspin 20 TM 30 kDa MWCO PES filters, centrifuged and transferred to pre-weighed 20 ml vials before freeze drying. The collagen samples are then combusted and converted to graphite for AMS measurement as described by Dunbar et al (2016). …”

“…For every batch of samples measured on the AMS, several standards are prepared and measured to produce a mean background value (Xu et al 2004;Naysmith et al 2010;Dunbar et al 2016). In order to obtain a representative bone background F 14 C value, sub-samples of an infinite age mammoth bone (LQH12) (confirmed in a previous study by Cook et al (2012)), are routinely prepared and measured along with every batch of bone samples (Dunbar et al 2016). In recent years (2011)(2012)(2013)(2014)(2015)(2016) we can see that there are more such observations for the wood rather than the bone samples, however, this might be expected since proportionately there are approximately 7 times more wood than bone samples in the series.…”