A low-cost and computer-controlled graphitization system connected to an elemental analyzer (EA) has been designed and built at the NTUAMS Lab. This semiautomatic system equips 6-unit reactors for the graphitization of CO2 with H2 on the iron catalyst. The entire procedure takes about 7 hours for iron conditioning, sample combustion and loading, and graphitization. The system can produce good-quality graphite for samples containing 0.5–1.6 mg carbon mass, with the pressure yield of graphitization ranging from 57.7% to 87.1%. The average values of OXI and OXII agree well with the consensus value, but the result of ANU sucrose was observed to be slightly higher than the reported one. The background samples of anthracite over ten months yielded an average of 0.38±0.10 pMC (n=21) corresponding to a 14C age of 45 kyr BP. Intercomparison samples L and M of FIRI exhibit that the measured 14C ages are almost identical to the consensus values and have a small spread in these values. The system has been carrying out graphitization for total organic carbon (TOC) of peat samples, and providing a more efficient and convenient way for AMS 14C dating.

Bone points were one of the major hunting implements in northern European hunter-gatherer societies. They differ in shapes, types, and manufacturing techniques. In this paper, we investigate 22 bone points from the territory of Lithuania, by studying their morpho-technological characteristics, direct dates, and adhesive residues. The majority are isolated finds, but four points were selected from excavated archaeological sites dated between the 5th and 3rd millennia cal BC. Most of the points belong to the barbed points category, but six slotted points were also studied. Of the 22, 16 previously undated points were sampled for accelerator mass spectrometry radiocarbon (AMS 14C) dating. The results of 10 successfully dated samples are discussed together with previously published 14C dates of bone points from the same region. ATR-FTIR analysis of adhesive residues from six points suggest that birch bark tar was used to haft barbed points and lithic inserts. The results reveal the diversity of types of Early Holocene bone points in the territory of Lithuania, while the slotted and Kunda-type bone points fall into narrow timeframes.

AMS radiocarbon dating has been widely applied in Palaeolithic art research and its value has been proven over the past three decades. Yet it still suffers from issues that need to be discussed and analysed to improve future sampling strategies and strengthen the interpretation of the results. This study presents new AMS dates for the parietal art in Cueva de Las Chimeneas in northern Spain, describes the quality of the samples, and discusses their reliability. The joint assessment of the dates and its comparison with previously obtained dates as well as stratified and dated portable art makes it possible to put forward a hypothesis about the time of creation of the cave's parietal art and the degree of synchrony or diachrony in its production. Consequently, it is proposed that the cave art at Las Chimeneas was created in the lower Magdalenian, between 19,000 and 17,500 cal bp.

Within the multidisciplinary WASA project, 160 cores up to 5 m long have been obtained from the back-barrier area and off the coast of the East Frisian island of Norderney. Thirty-seven contained basal peats on top of Pleistocene sands of the former Geest and 10 of them also had intercalated peats. Based on 100 acclerator mass spectrometry (AMS) 14C dates and analyses of botanical as well as zoological remains from the peats, lagoonal sediments and the underlying sands, a variety of distinct habitats have been reconstructed. On the relatively steep slopes north of the present island, a swampy vegetation fringe several kilometres wide with carrs of alder (Alnus glutinosa) moved in front of the rising sea upwards of the Geest as it existed then until roughly 6 ka, when the sea level reached the current back-barrier region of Norderney at around −6 m NHN (German ordnance datum). From then on for nearly 4000 years a changing landscape with a mosaic of freshwater lakes and fens existed within this area. It was characterised by various stands of Cladium mariscus (fen sedge), alternating with brackish reed beds with Phragmites australis (common reed) and salt meadows with Aster tripolium (sea aster), Triglochin maritima (sea arrowgrass), Juncus gerardii (saltmarsh rush) as well as mudflats with Salicornia europaea (common glasswort). As far as shown by our cores, this highly diverse, and for humans potentially attractive landscape was at least some 4 km wide and followed the coast for about 10 km. Before the rising sea caused diversification of habitats, wet heath as well as dry and dusty sand areas existed. In the course of time, parts of the wet heath turned into raised Sphagnum bogs under an oceanic precipitation regime before this diverse landscape was drowned by the rising sea and finally covered by marine sediments, while the earlier sediments and peats were partly eroded and redeposited.

Aeolian deposits are widely distributed in the middle Yangtze River Basin (YRB), central China. The formation of those aeolian deposits (including aeolian sands and loess deposits) represented the deterioration of local environment. Previous geochronological studies have shown that both aeolian sands and loess began to be deposited in the last interglacial (~100 ka). In this study, a total of four and six accelerator mass spectrometry radiocarbon (AMS 14C) samples were collected from a sand hill and a loess section, respectively, in the Jiujiang area to refine their chronology. Charcoals extracted from bulk samples were employed for AMS 14C dating. The sand layer at the lower part of the HG-C section is sandwiched by two mud layers dated to 26,670–26,285 and 24,480–24,180 cal BP, respectively. Therefore, we infer that aeolian activities in this region started at ~25 ka BP, which was significantly younger than that of previous studies. Meanwhile, thick loess began to deposit leeward of the sand hills in this region. Based on the AMS14C chronology and provenance tracing, we conclude that the loess was essentially the fine-grained aeolian deposits. Our results suggest that topography and vegetation cover have an important effect on the spatial distribution of aeolian deposits in this region.

This paper presents bulk stable isotope (δ13C, δ15N, C/N ratio) measurements of 14C dated carbonized crusts on 6th and 5th millennium cal BC pottery from Finland and northwestern Russia. Based on this data, it explores the differences in the origins of crusts attached on the inner and outer surfaces of vessels, and the changes in dietary practices and pottery use. It is argued that during the earliest phase of pottery use, mostly terrestrial ingredients were processed in the vessels, and aquatic resources became visible centuries later during the 5th millennium cal BC.

Applying radiocarbon (14C) dating using accelerator mass spectrometry (AMS) to the skeleton of a mammoth and the associated plant remains have been dated. The fossil of Zhalai Nur mammoth was dated to 43,500 +1000/–900 14C yr BP. The results of optically stimulated luminescence (OSL) dating, which show that a fluvially deposited gravel layer, from that the mammoth fossils were excavated, formed between 51,300±2100 and 26,600±1200 yr BP, place the new AMS 14C dates in a well-developed chronological framework. Through this study, it can be summarized that, firstly, using suitable sample material, it is possible to obtain reliable AMS 14C results, even when the ages of the target materials approach the upper limits of the method. Second, it reveals that a depositional hiatus exists during the Late Pleistocene, between ca. 26,000 yr BP and ca. 13,000 yr BP. Finally, large rivers and widely distributed areas of alluvial-fluvial deposits existed in this present-day desert area between ca. 51,000 and 26,000 yr BP. These results may shed new light on the study of the Mammuthus-Colelodonta-Bubalus fauna, the most important and fully developed fauna during the Late Pleistocene in northeastern China. They also deepen our understanding about the eco-environments of the region.

Paleoecological records from two Holocene peat bogs in northern Germany are linked by two microscopic volcanic ash layers, correlated by petrology and geochemistry to explosive volcanism on Iceland. The younger “Microlite tephra” cannot be correlated to any known eruption, while the older tephra layer is identified as a deposit of the Hekla 3 eruption. The tephra layers are dated by an age–depth regression of accelerator mass spectrometry 14C ages that have been calibrated and combined in probability distributions. This procedure gives an age of 730–664 cal yr B.C. for the “Microlite tephra” event and 1087–1006 cal yr B.C. for the Hekla 3 event. Accordingly, the tephra layers were deposited during the late Bronze Age. At this time, human settlement slowly increased pressure on the environment, as indicated by changes in woodland pollen composition at the two bogs. The tephra-marker horizons further show that the palynologically defined transition from the Subboreal to the Subatlantic Period is synchronous in the investigated area. However, the macroscopic visible marker in peat, the change from fibrous to sapric peat, the “Schwarztorf-Weißtorf-Kontakt,” is asynchronous. Bog vegetation did not immediately react in unison to a climatic change at this pollen zone boundary; instead, the timing of vegetation change depended on the location within the bog.

Computer models suggest that the Holocene Optimum for East Asian summer monsoon precipitation occurred at different times in different regions of China. Previous studies indicate that this time-transgressive Holocene Optimum should have been experienced about 3000 yr ago in southern China. In this study we describe a section which allows us to test this timing directly. We have closely examined high-resolution eutrophic peat/mud sequences covering the past 18,000 cal yr at Dahu, Jiangxi, on the southern boundary of the mid subtropical zone in China. Late Pleistocene successions in the Dahu record indicate cooler and much wetter conditions relative to synchronous events in north-central China. Our results indicate that the Holocene Optimum occurred between ca. 10,000 and 6000 cal yr ago in southern China, consistent with the global pattern. Conditions were relatively dry and cold from 6000 to 4000 cal yr ago. Our data also support the conclusion that the last deglaciation to early Holocene in the south was much wetter, resulting in the formation of dense broad-leaved forests, which could have acted to moderate land temperature ∼10,000 to 6000 cal yr ago, yielding a stable early-Holocene climate. After 6000 cal yr, forest reduction led to unstable land temperatures, and possibly to a northerly shift of the subtropical high-pressure system. Whatever the mechanism, these changes resulted in decreased precipitation between 6000 and 4000 cal yr B.P. in southern China.

The island fox (Urocyon littoralis) is one of few reportedly endemic terrestrial mammals on California's Channel Islands. Questions remain about how and when foxes first colonized the islands, with researchers speculating on a natural, human-assisted, or combined dispersal during the late Pleistocene and/or Holocene. A natural dispersal of foxes to the northern Channel Islands has been supported by reports of a few fox bones from late Pleistocene paleontological localities. Direct AMS 14C dating of these “fossil” fox bones produced dates ranging from ∼ 6400 to 200 cal yr BP, however, postdating human colonization of the islands by several millennia. Although one of these specimens is the earliest securely dated fox from the islands, these new data support the hypothesis that Native Americans introduced foxes to all the Channel Islands in the early to middle Holocene. However, a natural dispersal for the original island colonization cannot be ruled out until further paleontological, archaeological, and genetic studies (especially aDNA [ancient DNA]) are conducted.

This paper summarizes the present knowledge on the variation of summer temperatures in the European Alps throughout the Holocene by combining the results of an extraordinary archaeological find with the information gathered from glacier and tree-line movements. As it turns out, there were several distinct periods were the glaciers were smaller than today, allowing in some periods the growth of trees in areas, which even now are still covered with ice. On average, the first half of the Holocene was warmer than the second half, with temperatures starting to decrease around the time of the Iceman some 5000 yr ago. One of the coldest periods during the Holocene, the so-called Little Ice Age (LIA), lasted from about AD 1300 to 1850. It is well known that since then the Alpine glaciers have been receding, most likely amplified by anthropogenic impact. The study of temperature variations before human influence may help to eventually disentangle natural and anthropogenic causes for the global warming of our time.

Archaeologists have traditionally relied upon relative ceramic chronologies to understand the occupational histories of large and socially complex polities in the Maya lowlands. High-resolution accelerator mass spectrometry (AMS) radiocarbon dating can provide independent chronological control for more discrete events that reflect cultural change through time. This article reports results of AMS 14C dating of stratified sequences at the residential group Tzutziiy K’in, associated with the major Maya polity of Cahal Pech in the Belize Valley. Cahal Pech is one of the earliest permanently settled sites in the Maya lowlands (1200 cal BC), and was continuously occupied until the Terminal Classic Maya “collapse” (~cal AD 800). We use Bayesian modeling to build a chronology for the settlement, growth, and terminal occupation of Tzutziiy K’in, and compare our results to chronological data from the monumental site core at Cahal Pech. The analyses indicate that Tzutziiy K’in was first settled by the Late Preclassic period (350–100 cal BC), concurrent with the establishment of several other large house groups and the growth of the Cahal Pech site core. Terminal occupation by high-status residents at this house group occurred between cal AD 850 and 900. This study provides a framework for interpreting patterns of spatial, demographic, and sociopolitical change between households and the Cahal Pech site core.

The authors demonstrate the potential for dating structures in Near Eastern archaeology by applying AMS radiocarbon to organic inclusions found in mortar and plaster. The method was successfully applied to date and sequence excavated walls and floors, and to spot-date structures exposed in surveys.