The Middle Upper Palaeolithic (MUP) in eastern Central Europe (ECE) comprises three variants of Gravettian culture: Early Gravettian, Pavlovian, and Late Gravettian. While Early Gravettian and Pavlovian are merely located in Lower Austria and Moravia, the Late Gravettian occupations occurred over the entire territory of ECE. Compared to the number of sites the radiocarbon dating and the absolute chronology of the Late Gravettian is rather poor. The results presented here bring a new set of radiocarbon (14C) dates for the Late Gravettian period in ECE and propose that this period began and ended earlier than previously suggested.

The Δ14C content of surface waters in and around the Cariaco Basin was reconstructed from radiocarbon measurements on sub-annually sampled coral skeletal material. During the late 1930s to early 1940s, surface waters within and outside of the Cariaco Basin were similar. Within the Cariaco Basin at Islas Tortugas, coral Δ14C averages −51.9 ± 3.3%. Corals collected outside of the basin at Boca de Medio and Los Testigos have Δ14C values of −53.4 ± 3.3% and −54.3 ± 2.6, respectively. Additional 14C analyses on the Isla Tortugas coral document an ∼11% decrease between ∼1905 (−40.9 ± 4.5%) and ∼1940. The implied Suess effect trend (−3%/decade) is nearly as large as that observed in the atmosphere over the same time period. If we assume that there is little to no fossil fuel 14CO2 signature in Cariaco surface waters in ∼1905, the waters have an equivalent reservoir age of ∼312 yr.

We analyze here the time record of total carbonate carried as CaCO3 in a sea-bottom core from the Ionian Sea. Several major periods appear, most strongly at 1100, 690, 500, 340, 250 and 90 yr, confirmed both in the periodogram and maximum entropy estimates. The Gleissberg period appears in common with the 14C and other records, such as the sunspot index and aurorae. The manifestation of this period in what we surmise to be a climatic record is further evidence that the Gleissberg period has correlated bolometric and electrodynamic aspects.

The construction and performance of a proportional CO2 counter system is described by which an over-all accuracy is obtained of 1.3‰ after a two-day counting period.

During the last three years the ETH-EN-tandem accelerator facility has been adapted for the quantitative determination of the rare isotopes 14C and 10Be in mg samples. The goal of this project is to routinely achieve a 1% accuracy when measuring 14C/12C ratios with a minimum expenditure of human resources and beam time. The concept is similar to that proposed by Purser and Henley (1978). The early evolution of this dating facility was described previously (Suter et al, 1981a,b). This paper is a brief report on the current status of the system and its development.

Primary and secondary standards are essential in radiocarbon analyses for the purpose of reporting and comparing data among laboratories, as well as for internal laboratory data quality control. ANU sucrose is one of the IAEA-certified 14C standards (C-6) with a consensus value of 1.5061 ± 0.0011 fraction modern (Fm). All of our measurements of ANU sucrose (n = 351) as a secondary standard over the last 7 yr result in an average value of 1.5016 ± 0.0005 Fm (2-σ standard error). After applying the same outlier tests used for IAEA reference standards, a weighted average value of 1.5016 ± 0.0002 Fm (n = 294) was calculated. This value is significantly lower than the IAEA C-6 consensus value (t test with unequal variance; p = 0.023). In contrast, our measurements of other secondary standards over the same time period are in excellent agreement with their respective consensus values. Since ANU is the only secondary standard measured in our lab that does not agree with the consensus values, and we have measured a larger number analyses compared to what went into the definition of the consensus value, we suggest that the consensus value of ANU sucrose might be too high by ∼0.0045 ± 0.0011 Fm. Given that some labs routinely use ANU sucrose as a primary standard, our results suggest that revisiting the consensus value of ANU sucrose may be necessary.

The Caribbean Archaic Age (about 3000–500 BC) is thought to represent the earliest migration of humans from South America into the Lesser Antilles. However, there is a conspicuous absence of these early sites on islands south of the Guadeloupe Passage. To date, only a single radiocarbon date derived from a Queen conch (Strombus [Eustrombus] gigas) shell at the Heywoods site on Barbados was indicative of an Archaic occupation in the southern Antilles apart from a scattering of poorly reported (and mostly undated) sites. Given a number of issues associated with reliance on a single date to establish a cultural horizon, along with other problems derived from possible carbonate cement contamination and dating marine shells of a longer-lived species such as Queen conch, 2 additional samples were taken from the same unit and context at Heywoods to confirm whether the site is truly representative of an occupation during the Archaic Age. Results from a Queen conch shell adze in Context 7 dated to 2530–2200 BC (2 σ) and overlaps with the only other Archaic date from the site dating to 2320–1750 cal BC, while a juvenile specimen of the same species from Context 8 at 3280–2940 BC (2 σ) indicates that Barbados may have been settled even earlier. This suggests that Heywoods may be the oldest site between Trinidad and Puerto Rico. While further confirmation is required, these new dates have implications for understanding the nature of migratory ventures in the Caribbean, such as whether the “Southward Route” hypothesis—which postulates that earlier migration events from South America during the Ceramic Age (beginning ∼500 BC) initially bypassed the southern Lesser Antilles—also applies to the Archaic, and if other phenomena such as active volcanism may have played a role in structuring settlement patterns. Questions also remain as to why Heywoods does not exhibit the typical lithic Archaic tool kit.

This date list covers age measurements carried out at the Radiocarbon Dating Laboratory of the German Academy of Sciences of Berlin (DAW) since 1963 and is a continuation of our first date list (Berlin I). Procedures and methods of preparing the samples are essentially the same. We completed our laboratory with a second electronic counting apparatus. Two further proportional counters with internal anticoincidence (Houtermann-Oeschger counters) are made from an old railway-car axle. The total volume of these counters is 4 L, the effective volume 2.2 L, the background 2.0 counts/min at 700 Torr (acetylene filling), and the contemporary standard value (0.95 NBS oxalic acid) is 20 counts/min. Each sample is measured twice, first for 48 hr and after 8 days for another 24 hr. Data have been calculated on the basis of a C14 half-life of 5570 yr (Godwin, 1962). Errors listed include the standard deviations (1σ) of the counting rates of the contemporary samples, the background and the unknown samples. Calculated errors less than 100 yr have been increased to that figure as a minimum.

Corrections have not been made for C13 content. Mass spectrometrics C13 measurements of some samples indicate that errors resulting from fractionation are minimal.

We report the first attempt to date Icelandic groundwater by the radiocarbon dating technique. We propose that boron concentrations of the water samples can be taken as a measure of the amount of dead CO2 in the groundwater leached from rock. By assuming that the ratio of boron to CO2 is the same in the rock and groundwater it is possible to correct the 14C concentration for the contribution of rock-derived carbon in the groundwater and thus calculate the initial (undiluted) 14C concentration. When this correction is applied, the values for the cold and warm waters lie in the range 60 to 110 pMC, which is in accordance with the estimated residence time for the groundwater. We have also calculated the fractions of atmospheric and organic carbon in the water, based on the δ13C measurements, and the results agree well with the general hydrology and vegetational cover of the areas. Results from geothermal systems indicate that it is possible to use 14C to estimate relative age differences of the water in a particular geothermal area.

Over the last few decades, radiocarbon laboratories have used different procedures for measuring a broad range of carbonaceous materials. To produce reliable results, the processes employed for sample processing, graphite target production, and spectrometer measurement must be rigorous, well tested, and reproducible. Most of the procedures have been developed, improved, and published as part of the laboratories’ quality control and research programs, and can be frequently found in the literature. Nevertheless, there are suites of laboratory techniques (or “small useful skills”), products, and other resources that either have never been described in publications, or have been somewhat hidden in much larger scientific articles and reports. We feel that with the rapid rise of newer laboratories and facilities, a set of resourceful suggestions might come in handy. Here we gathered these skill sets that can be used in all aspects of 14C sample processing, with the intention to simplify and expedite procedures, from glass-tube making to graphitization and measurements. We also included some miscellaneous items to help in laboratory setup.

The Royal Institute for Cultural Heritage (RICH) radiocarbon (14C) laboratory in Brussels, Belgium, has acquired experience for pretreating samples with 60 years of involvement in 14C dating, and the implementation of routine protocols. These procedures as applied to wood, seeds, charred materials, bones, ivory, textiles (silk, wool, cotton, linen), paper, shells, cremated bones, mortars, lead carbonates, sediments, etc. are described in detail in this paper. They are evaluated against reference materials.

In the Great Basin of North America, big sagebrush (Artemisia tridentata Nutt.) growth rings can be used to reconstruct environmental changes with annual resolution in areas where there is otherwise little such information available. We tested the annual nature of big sagebrush wood layers using accelerator mass spectrometry (AMS) radiocarbon dating. Four cross-sections from 3 sagebrush plants were collected near Ely, Nevada, USA, and analyzed using dendrochronological methods. Ten 14C measurements were then used to trace the location of the 1963–64 “bomb spike.” Although the number of rings on each section did not exceed 60, crossdating was possible within a section and between sections. Years assigned to individual wood layers by means of crossdating aligned with their expected 14C values, matching the location of the 14C peak. This result confirmed the annual nature of growth rings formed by big sagebrush, and will facilitate the development of spatially explicit, well-replicated proxy records of environmental change, such as wildfire regimes, in Great Basin valleys.

Radiocarbon analyses of 14 modern, pre-bomb marine organisms collected between AD 1836 and 1946 along the eastern Adriatic coast were performed. The 14C ages of five algal and nine mollusk samples were measured by accelerator mass spectrometry (AMS). Marine 14C reservoir ages (R) and regional offsets (ΔR) were calculated and compared. The marine reservoir ages of shells and algae significantly differ, even though both inhabit the hard substrate from the intertidal zone to shallow sea. Coralline algae had a considerably lower reservoir age (355 ± 34 14C yr) and ΔR value (–9 ± 34 14C yr) than mollusks (R 513 ± 53 14C yr; ΔR 154 ± 52 14C yr), though the variability of R was high in both groups. Although the microlocations of pre-bomb samples were not known and the studied mollusk species are able to inhabit marine or estuarine environments, it can be assumed that they were not significantly influenced by a freshwater admixture, due to their δ13C values being mostly in the marine range. However, as the entire eastern Adriatic is formed in carbonates, mollusk shells could be influenced by limestone-depleted 14C. In examining new data together with previously published data, the marine reservoir effect (MRE) for the Adriatic area is estimated to be 424 ± 57 14C yr (ΔR is 77 ± 57 14C yr). Without mussel shells, the estimated MRE is 378 ± 44 14C yr (ΔR is 28 ± 45 14C yr). The presented values are comparable to the MREs and mean ΔRs obtained for the Mediterranean by other authors.

For radiocarbon calibration, the arrow of time is pointing backwards but the entropy does not necessarily decrease in this direction…

A formally modeled radiocarbon chronology for a new profile through the great Neolithic tell of Vinča-Belo Brdo, Serbia, is the third interwoven strand in refining the chronology of the tell. This now joins models for the whole sequence based on the archive of early excavations, and for the last two known horizons at the top of the settlement mound, investigated in recent decades. In the new deep sounding, Vinča culture occupation from the 52nd century cal BC is slightly later than in the main sequence, probably reflecting the horizontal extension of the tell as it began to grow. The last dated occupation falls in the late 47th–early 46th century cal BC, slightly earlier than in the main sequence, but the top of the profile is affected by the slippage that caused the new excavations. Formal estimates are given for the succession and varying durations of burnt and unburnt houses, and indicate a period in the first part of the 5th millennium without house burning. Overall, the combined results from the three interwoven strands serve to produce a radically enhanced understanding of the temporality of the tell, which builds on, rather than supplants, previous research. We knew previously that Vinča-Belo Brdo was very long-lived, but now we can time that history with much greater precision. We can assert with much greater confidence that its vertical buildup was steady and largely uninterrupted. We have begun, from the work on the top of the tell and in the new deep sounding, to grasp better the fluctuations in house durations from generation to generation, and can now contrast the relative fortunes of unburnt and burnt houses. We can say much more about the timing and tempo of the ending of the tell, and about the possible circumstances in which that took place.

The half-life of radiocarbon (14C) is 5700 ± 30 yr, which makes it particularly useful for dating in archaeology. However, only an exceptional hindrance of the beta decay from 14C to 14N—a so-called Gamow-Teller ß-decay—makes this half-life so long. A normal strength would result in a half-life of only a few days, completely useless for archaeological dating. The unusual hindrance is based on the nuclear structure of the two nuclei, resulting in strongly destructive interferences of the nuclear transition matrix element. Nuclear model calculation with great computational efforts have been performed in the literature to reproduce the very low transition probability. Here, we will attempt to describe the nuclear physics behind this most unusual half-life.

The Swedish varve chronology, or Swedish Time Scale, is an annual chronology based upon the successive correlation of more than 1000 varve-thickness diagrams. The Late Glacial-Early Holocene varved clays were deposited as glaciolacustrine sediments in the Baltic Sea during the recession of the Scandinavian ice sheet. Formation of varved clays continued throughout the Holocene and is still going on in the estuary of River ångermanälven in northern Sweden. Accelerator mass spectrometry (AMS) radiocarbon measurements, which have been performed on terrestrial plant macrofossils extracted from the varved clays, show—in comparison with other annual chronologies—that several hundreds of varve years are missing in the varve chronology. These findings are supported by, among others, pollen stratigraphic investigations on time-equivalent varve year intervals. If an effort were undertaken to evaluate the erroneous parts, the Swedish Time Scale would have the potential of becoming a continuous annual chronology.

The following is a list of dates obtained since the time of the compilation of List IX in December 1963. The method is essentially the same as that used for the work described in the previous list. Two CO2-CS2 Geiger counter systems were used. The equipment and counting techniques have been described elsewhere (Crane. 1961a, 1961b). The dates and estimates of error in this list follow the practice recommended by the International Radiocarbon Dating Conference of 1962, in that (a) dates are computed on the basis of the Libby half-life, 5570 yr, (b) a.d. 1950 is used as the zero of the age scale and (c) the errors quoted are the standard deviations obtained from the numbers of counts only. In previous Michigan date lists up to and including VII we have quoted errors at least twice as great as the statistical errors of counting, in order to take account of other errors in the over-all process. If the reader wishes to obtain a standard deviation figure which will allow ample room for the many other sources of error in the dating process, we suggest he double the figures that are given in this list.

Chemical pretreatment procedures for the decontamination, extraction, and isolation of organic materials for 14C dating using the Oxford accelerator system are described. Specific details are given for the isolation and chromatographic purification of amino acids from bone and tooth collagen, of lipids from sediments, and of cellulose and glucose from wood, paper, and textiles. A description is also given of the apparatus used for the routine preparation of 1 to 5mg graphite samples on tantalum wire, for use in the accelerator ion source.

The high energy mass spectrometer (HEMS) approach to 14C dating allows the use of very small samples in the low milligram range. Sample pretreatment and decontamination procedures can be both more vigorous and more selective than those used by conventional dating laboratories. Specific chemical compounds can be isolated from archaeologic or geologic samples; such compounds may be characteristic of particular source materials and, hence, provide more detailed information than is generally possible using bulk organic samples. The Oxford Radiocarbon Unit has concentrated on three sample types that represent the kind of material we expect to work on initially: bone, lake sediment, and wood.

Carbon isotope ratios were measured in organic and inorganic carbon of settling particulate matter collected with a sediment trap at Ocean Station “P” in the Gulf of Alaska from March to October, 1983. Dissolved inorganic carbon (DIG) in surface sea water collected during two different seasons in 1984 were analyzed using large gas proportional counters and revealed a minimum seasonal Δ14C variation of 14‰. Results show that the Δ14C of calcium carbonate scdimenting to the deep sea is the same as that measured in surface water DIC. In contrast, particulate organic carbon (POC) had significantly higher Δ14C values (by 25–70‰) than that in surface water DIC. Also, the δ13C of the POC was markedly lower than previously reported values from other trap stations and marine particulate matter in general. Results from this study suggest that a significant amount of the POC settling to the deep sea at this pelagic station is of terrestrial origin, not strictly of marine origin as had previously been believed.