Prof Christopher Ramsey

Abstract:

The Lake Suigetsu SG06 sedimentary archive from Honshu Island, central Japan, provides a high-resolution palaeoenvironmental record, including a detailed record of explosive volcanism from Japan and South Korea. Thirty visible tephra are recorded within the 73 m-long SG06 core, which spans the last ∼150 ka. Here we describe and characterise these tephras based on major element glass composition, which is useful for the identification and correlation of these tephras and the age models of the records in which they are found. Utilising the large number of radiocarbon measurements (n > 600) from terrestrial plant macrofossils in the Lake Suigetsu SG06 record, we are able to provide precise and accurate ages for the tephras from eruptions within the last 50 ka. Glass compositional data of some of the largest eruptions from Japan (K-Ah, AT, Aso-4, Aso-A, Aso-D, and Ata; sampled at proximal outcrops) are also presented. These data show that the major element glass chemistry is distinctive for many of the visible SG06 tephra units, and allows some of the layers to be correlated to known eruptions from volcanoes in Japan and South Korea, namely K-Ah (SG06-0967), U-Oki (SG06-1288), AT (SG06-2650), Aso-4 (SG06-4963/SG06-4979), K-Tz (SG06-5181), Aso-ABCD (SG06-5287) and Ata (SG06-5181). The following ages were obtained for the SG06 tephra units: 3.966-4.064 cal. ka BP (95.4% probability range) for the SG06-0588 tephra, 10.242-10.329 cal. ka BP (95.4% probability range) for SG06-1293, 19.487 ± 112 SG062012 ka BP (2 σ) for SG06-1965, 28.425 ± 194 SG062012 ka BP (2 σ) for SG06-2504, 28.848 ± 196 SG062012 ka BP (2 σ) for SG06-2534, 29.765 ± 190 SG062012 ka BP (2 σ) for SG06-2601, 29.775 ± 191 SG062012 ka BP (2 σ) for SG06-2602, 43.713 ± 156 SG062012 ka BP (2 σ) for SG06-3485, 46.364 ± 202 SG062012 ka BP (2 σ) for SG06-3668, 49.974 ± 337 SG062012 ka BP (2 σ) for SG06-3912, 50.929 ± 378 SG062012 ka BP (2 σ) for SG06-3974, and improved ages for two of the most important tephra markers across Japan, the K-Ah (7.165-7.303 cal. ka BP at 95.4% probability range; SG06-0967) and AT tephra (30.009 ± 189 SG062012 ka BP at 2 σ; SG06-2650). © 2013.

Abstract:

We report variations in age of recent batches of ultrafilter humectant, and also clarify the pore size of Ezeefilters™ used at the Oxford Radiocarbon Accelerator Unit (ORAU). © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.

Abstract:

Only a few astrophysical points and synchronisms listed in texts provide anchor points for the absolute chronology of Ancient Egypt. At first we will show how we can re-calculate some of these anchor points by using Sothic dating based on the arcus visionis method, and modelling lunar dates using a Bayesian approach. Then, we will discuss two radiocarbon studies carried out on short-lived Egyptian materials held at the Louvre Museum that could be attributed to particular reigns or other precise periods. Using a Bayesian approach, these dates were combined with the known order of succession and the lengths of reigns. Sothic and lunar dates were integrated as priors in the model. This approach has led to a new proposal for the absolute chronology of Egypt's 18th Dynasty. © 2012 Elsevier Ltd.

Abstract:

This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art - from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial 'set', each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists. © 2013.

Abstract:

The Neolithic settlement of Alsónyék reached its greatest extent during the Late Neolithic Lengyel period. Nearly 9000 features, including postholes associated with 122 houses, pits and pit complexes, and c. 2300 burials, could be assigned to it. The traces of Lengyel settlement and burials were found over the entire excavated area, with an estimated extent of some 80 ha. The burials uncovered mostly form part of groups of graves, actually being small cemeteries within the various parts of the settlement. Apart from the grave groups, several solitary or scattered graves were also found. Other large Lengyel burial grounds or large Lengyel settlements with numerous burials are known in Transdanubia, but the enormous number of graves at Alsónyék is unprecedented within the Lengyel cultural complex as a whole, and provides exciting opportunities for varied archaeological and bioarchaeological investigations. The discovery of 122 surface-level, timber-framed houses at a single site is also unique for the area and the Lengyel period as a whole. These buildings help to build a better understanding of the architecture and lifestyle of the Lengyel population, which is a fairly new strand in the settlement archaeology of the Lengyel culture in Hungary and beyond. This and the sheer size of the site make Alsónyék exceptionally significant. Altogether 217 radiocarbon results are presented for the Lengyel phase. For the purpose of analysis subsites 5603, 11 and 10B have been modelled separately. The modelled estimates are precise enough that it is possible to estimate robustly the timing of activity across the site. The modelling suggests that burial activity in subsite 5603 probably began in 4790-4740 cal BC (68% probability) and that it began at a similar time, 4795-4745 cal BC (68% probability), in subsite 11. An intensive period of burial began slightly later, in 4715-4690 cal BC (68% probability), on subsite 10B. At this time settlement was established across a wide area, in subsite 11 from 4745-4690 cal BC (68% probability), on subsite 5603 from 4745-4665 cal BC (68% probability), and on subsite 10B from 4720-4700 cal BC (68% probability). After a brief episode of intense occupation, lasting at most a few decades, settlement and then burial ended on the northernmost subsite 10B, in the 4700s or 4690s cal BC (68% probability) and 4695-4670 cal BC (68% probability) respectively. Settlement also ended before burial on subsite 11, but endured for much longer. The settlement here ended in 4670-4620 cal BC (37% probability) or 4610-4565 cal BC (31% probability) and burial in 4585-4515 cal BC (68% probability). Both settlement and burial endured longest on sub-site 5603, although here the end of burial preceded the end of settlement by well over a century. Burial ended here in 4515-4465 cal BC (68% probability), and settlement ended in 4345-4245 cal BC (68% probability).