Radiocarbon Dating and Intercomparison of Some Early Historical Radiocarbon Samples

Abstract

We performed a new series of measurements on samples that were part of early measurements on radiocarbon (14C) dating made in 1948–1949. Our results show generally good agreement to the data published in 1949–1951, despite vast changes in technology, with only two exceptions where there was a discrepancy in the original studies. Our new measurements give calibrated ages that overlap with the known ages. We dated several samples at four different laboratories, and so we were also able to make a small intercomparison at the same time. In addition, new measurements on samples from other Egyptian materials used by Libby and co-workers were made at UC Irvine. Samples of tree rings used in the original studies (from Broken Flute Cave and Centennial Stump) were obtained from the University of Arizona Laboratory of Tree-Ring Research archive and remeasured. New data were compared to the original studies and other records.

Radiocarbon dating

“…Protection and conservation studies of tangible cultural heritage frequently use radiocarbon dating, although historic data often provide the chronological context for many items. The first radiocarbon dating studies published in 1949 as a part of curve of knowns [G] 3 included acacia wood from the tomb of Pharaoh Zoser (Djoser), as well as a range of archaeological textiles and wood from Egypt and North and South America 3, 262,263 . Considering that the technological developments at the time meant that several grams of material were required, the sacrifice was remarkable.…”

Vegetation response to the Indian Summer Monsoon (ISM) variability during the Late-Holocene from the central Indian core monsoon zone

“…This resulting carbon dioxide was collected and converted to acetylene, which is trimerized to benzene using catalyst V 2 O 5 . The counting was carried out on a Liquid Scintillation Counter (Quantulus 1220) (Jull et al, 2018; Van Der Plicht and Hogg, 2006).…”

AN INTERCOMPARISON PROJECT ON 14C FROM SINGLE-YEAR TREE RINGS

“…All laboratories use international secondary standards, such as IAEA-C3, IAEA-C7 and IAEA-C8, as well as wood-blank materials, including charcoal, oak (see e.g., Jull et al 2018b;Fogtmann-Schultz et al 2019;Kudsk et al 2019) and Brown Coal. At AARAMS, 14 C ages are calculated using an in-house graphical normalization program in Matlab, whereas Arizona uses the in-house software and methods described in Donahue et al (1990) and Burr et al (2007).…”

“…The geometric mean and scatter of the processed IAEA-C9 samples (F 14 C = 0.0016 ± 0.0003, n=3) and IAEA-C3 samples (F 14 C = 1.2929 ± 0.0019, n=3) from HEKAL were in good agreement with their consensus values. Other intercomparisons of HEKAL wood preparation and AMS 14 C analyses were recently reported by Jull et al (2018b). For all three laboratories, the uncertainty of the primary standard (OX-II) and blank samples is included in the analytical result using propagation of errors.…”