bluuebunny/crossref_metadata_2025 huggingface dataset:
A Gas Ion Source for Radiocarbon Measurements at 200 kV
Authors: Ruff M , Wacker L , Gäggeler H W , Suter M , Synal H-A , Szidat S
Published: July 2016

The novel tabletop miniaturized radiocarbon dating system (MICADAS) at ETH Zurich features a hybrid Cs sputter negative ion source for the measurement of solid graphite and gaseous CO2 samples. The source produces stable currents of up to 6 μA C− out of gaseous samples with an efficiency of 3–6%. A gas feeding system has been set up that enables constant dosing of CO2 into the Cs sputter ion source and ensures stable measuring conditions. The system is based on a syringe in which CO2 gas is mixed with He and then pressed continuously into the ion source at a constant flow rate. Minimized volumes allow feeding samples of 3–30 μg carbon quantitatively into the ion source. In order to test the performance of the system, several standards and blanks have successfully been measured. The ratios of 14C/12C could be repeated within statistical errors to better than 1.0% and the 13C/12C ratios to better than 0.2%. The blank was <1 pMC.
Radiocarbon Intercomparison Program for Chauvet Cave
Authors: Cuzange Marie-Thérèse , Delqué-Količ Emmanuelle , Goslar Tomasz , Grootes Pieter Meiert , Higham Tom , Kaltnecker Evelyne , Nadeau Marie-Josée , Oberlin Christine , Paterne Martine , van der Plicht Johannes , Ramsey Christopher Bronk , Valladas Hélène , Clottes Jean , Geneste Jean-Michel
Published: July 2016

We present the first results of an accelerator mass spectrometry (AMS) radiocarbon intercomparison program on 3 different charcoal samples collected in one of the hearths of the Megaceros gallery of Chauvet Cave (Ardèche, France). This cave, rich in parietal decoration, is important for the study of the appearance and evolution of prehistoric art because certain drawings have been 14C dated to the Aurignacian period at the beginning of the Upper Paleolithic. The new dates indicate an age of about 32,000 BP, which is consistent with this attribution and in agreement with the results from the same sector of the cave measured previously at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE). Six laboratories were involved in the intercomparison. Samples were measured in 4 AMS facilities: Center for Isotope Research, Groningen University, the Netherlands; the Oxford Radiocarbon Accelerator Unit, UK; the Centre de datation par le carbone 14, Univ. Claude Bernard Lyon 1, France (measured by AMS facilities of Poznań University, Poland); and the LSCE, UMR CEA-CNRS-UVSQ, France (measured by the Leibniz-Labor of Christian-Albrechts-Universität Kiel, Germany).
A Comparison of Radiocarbon and Archaeomagnetic Dating from an Archaeological Site in Spain
Authors: Catanzariti G , McIntosh G , Osete M L , Nakamura T , Rakowski A Z , González I Ramírez , Lanos Ph
Published: July 2016

Reference archaeomagnetic secular variation (SV) curves recently have been proposed for the Iberian Peninsula and may now be used for archaeomagnetic dating. Archaeomagnetic dating is a relative dating technique that is strongly dependent on the age control of the data used to construct the reference curves. In order to test the method, an archaeological structure from central Spain has been studied. Samples have been taken for both archaeomagnetic and radiocarbon dating, and the results are compared. Close agreement is observed between both techniques, with the archaeomagnetic age of AD 603–999 overlapping the calibrated age of AD 770–890. These results demonstrate the reliability of the proposed reference curves as a dating tool within the Iberian Peninsula during this archaeological period.
Radiocarbon Chronology of the Ancient Settlement in the Golan Heights Area, Israel
Authors: Nawrocka Danuta Michalska , Michczyńska Danuta Joanna , Pazdur Anna , Czernik Justyna
Published: July 2016

Carbonate binders from mortars and plasters as well as charcoal fragments sampled at the ancient settlement of Hippos (Sussita) have been subjected to radiocarbon dating by gas proportional counting (GPC) and accelerator mass spectrometry (AMS). Hippos is situated on the east coast of the Sea of Galilee (32°46′N, 35°39′E) at the top of a hill in the Golan Heights area, Israel. According to historical-archaeological data, the town had functioned since the 3rd century BC until AD 749, when it eventually crumbled into ruins after an earthquake. The appropriate sample selection and preparation based on the results of petrographic observations permitted us to distinguish different phases involved in the expansion of the settlement. More than 200 samples were taken from the settlement and subjected to petrographic and chemical analyses. Of the 200 total samples, about 20 were selected for dating. Here, we present the first 10 results of14C dating carried out for Hippos. The oldest sample dated thus far gave an age corresponding with the 2nd century BC to 1st century AD—probably indicating an old Roman temple, on the base of which the North-West church (NWC) was later erected. The next dates extend up to the 8th century AD, the age related to the last phase of settlement inhabitation. Research is continuing as new excavations take place.
Implication of Radiocarbon Dates from Sohr Damb/Nal, Balochistan
Authors: Görsdorf Jochen , Franke-Vogt Ute
Published: July 2016

Sohr Damb/Nal, the type site of the Nal complex, is located in Balochistan, Pakistan. After 1 season of excavation by H Hargreaves in 1924, which made the polychrome Nal pottery widely known, no further work took place until the Joint German-Pakistani Archaeological Mission to Kalat resumed excavations in 2001. So far, 4 seasons of excavations have been undertaken, which have revealed 4 periods of occupation, dated from about 3800 to 2000 BC. The well-stratified assemblages provide new insights into cultural processes and developments, and enhance the comparative frameworks through typological series and a comprehensive set of radiocarbon dates. This information is essential for assessing cross-cultural relations and the date of urbanization. In this paper, the 14C dates from Sohr Damb/Nal are presented and their cultural context is discussed. Period III has several links to sites in Pakistan, Afghanistan, and Iran, such as Miri Qalat IIIb–c, Mehrgarh VI–VII/Nausharo I, Quetta III, Mundigak IV, and Shahr-e Sokhta II–III. Period IV represents a Kulli-Harappan occupation, which is dated to the second half of the 3rd millennium BC.
The Catacomb Cultures of the North-West Caspian Steppe: 14C Chronology, Reservoir Effect, and Paleodiet
Authors: Shishlina N I , van der Plicht J , Hedges R E M , Zazovskaya E P , Sevastyanov V S , Chichagova O A
Published: July 2016

For the Bronze Age Catacomb cultures of the North-West Caspian steppe area in Russia, there is a conflict between the traditional relative archaeological chronology and the chronology based on radiocarbon dates. We show that this conflict can be explained largely by the fact that most dates have been obtained on human bone material and are subject to 14C reservoir effects. This was demonstrated by comparing paired 14C dates derived from human and terrestrial herbivore bone collagen. In addition, values of stable isotope ratios (δ13C and δ15N) and analysis of food remains from vessels and the stomach contents of buried individuals indicate that a large part of the diet of these cultures consisted of fish and mollusks, and we conclude that this is the source of the reservoir effect.
Carbon Isotopes in Tree Rings: Climate and the Suess Effect Interferences in the Last 400 Years
Authors: Pazdur Anna , Nakamura Toshio , Pawełczyk Sławomira , Pawlyta Jacek , Piotrowska Natalia , Rakowski Andrzej , Sensuła Barbara , Szczepanek Małgorzata
Published: July 2016

New records of δ13C and Δ14C values in annual rings of pine and oak from different sites around the world were obtained with a time resolution of 1 yr. The results obtained for Europe (Poland), east Asia (Japan), and South America (Peru) are presented in this paper. The δ13C and radiocarbon concentration of α-cellulose from annual tree rings of pine and of the latewood of oak were measured by both accelerator mass spectrometry (AMS) and liquid scintillation spectrometry (LSC). The values of 14S, which represent decreasing 14C concentrations caused by the emission of CO2 from fossil fuel use (Suess effect; Suess 1955), were calculated for each site. Low average 14S (about −0.4 to 0.8%) values for clean areas and high values (about 3.4–3.6%) for industrial and/or urbanized areas were noted. Records of the δ13C values obtained for pine and oak from Poland were used to reconstruct climate changes during the last 400 yr. The results clearly indicate the climate cooling during the periods of the Maunder minimum (1645–1715) and the Dalton minimum (1790–1820). The anti-correlation between the δ13C and Δ14C records during those 2 periods is clear if the 14C record is shifted toward older ages by 24 yr.
Radiocarbon Age Anomalies in Pre- and Post-Bomb Land Snails from the Coastal Mediterranean Basin
Authors: Quarta G , Romaniello L , D'Elia M , Mastronuzzi G , Calcagnile L
Published: July 2016

The shell carbonate of pre- and post-bomb samples of 2 species of terrestrial gastropods (Theba pisana and Cernuella virgata) sampled along the coast of Apulia, southern Italy, were dated using accelerator mass spectrometry and carbon stable isotopes were analyzed. The analyses show, for both species, significant anomalies in the radiocarbon age due to the possible presence of a 14C-depleted source of carbon in the formation of the shell aragonite. The magnitude of the age anomaly was quantified in the studied area to ∼1000 14C yr.
14C-Dated Charcoal and Sediment Drilling Cores as First Evidence of Holocene Tsunamis at the Southern Spanish Coast
Authors: Becker-Heidmann Peter , Reicherter Klaus , Silva Pablo G
Published: July 2016

At 2 locations of the southern Spanish coast, we found indications for tsunamis induced by submarine earthquakes. Charcoal, which we sampled in 2 stratified, assumed tsunamigenic sediment (tsunamites) layers at the shore outside the ruins of the Roman city of Baelo Claudia, close to the Strait of Gibraltar (province of Cádiz), and radiocarbon dated, surprisingly turned out to be of identical age, about 465 BP. In the laguna of the Cabo de Gata (province of Almería), we found possible remnants of tsunamites in drilling cores deposited above organic sediments, 14C dated as 680 ± 30 BP.
Tropical South China Sea Surface 14C Record in an Annually-Banded Coral
Authors: Mitsuguchi Takehiro , Dang Phong X , Kitagawa Hiroyuki , Yoneda Minoru , Shibata Yasuyuki
Published: July 2016

A surface-water Δ14C record of AD 1948–1999 in the tropical South China Sea (SCS) has been reconstructed from accelerator mass spectrometric radiocarbon measurements of annual bands of a Pontes coral collected from Con Dao Island, Vietnam. Results gave the following Δ14C time series: a steady state of −47.8 ± 2.8‰ (mean ± SD, n = 8) during 1948–1955 (i.e. in the pre-bomb period); a sharp increase during 1956–1966; a gradual increase during 1967–1973; a relatively high maximum value of ∼174‰ in 1973; and a gradual decrease for the following period to ∼86‰ in 1999. This Δ14C record having a sharp increase and a relatively high peak is similar to the records of subtropical corals (latitudes 21–27°) and is distinctly different from the records of equatorial/tropical corals (latitudes <10°), although our coral sample was collected from an equatorial/tropical region (8°39′N, 106°33′E). This can be explained by the geographic, oceanographic, and climatic setting of our study site. The SCS is a semi-enclosed marginal sea in the far western tropical Pacific and is little influenced by equatorial upwelling or related ocean currents. Our study site is located in the southwestern SCS, where an enormous submerged plain (the Sunda Shelf) spreads out with very shallow waters (mean depth <100 m). Furthermore, in the SCS, the East Asian monsoon (a strong, seasonally reversing wind system) enhances air-sea gas exchange especially in the mainland coastal waters, including our study site. Such semi-enclosed shallow waters with enhanced ventilation were probably very sensitive to the atmospheric nuclear explosions in the late 1950s and early 1960s and caused the sharp increase and high peak in the coral Δ14C record. Our coral Δ14C values in the southwestern SCS are significantly higher than the values in the northwestern SCS (Xisha Islands), which seems to suggest that meridional mixing of surface waters is not active in the SCS and that the open-ocean water intruding into the northern SCS (i.e. the Kuroshio intrusion) has only a limited influence on the southern SCS.
Reservoir Effect of Coastal Waters Off Western and Northwestern Galicia
Authors: Soares António M Monge , Dias João M Alveirinho
Published: July 2016

Differences in the radiocarbon ages of closely associated marine mollusk shells and terrestrial material (charred wood or bones) from several Galician archaeological contexts are significant from the Iron Age to Medieval times. δR values show high variability, ranging from −280 ± 70 to 270 ± 40 14C yr. The set of δR values also presents a strong positive peak (δR = 270 ± 40 14C yr) at 860 ± 90 BP, which matches another peak found for western Portuguese coastal waters. The data obtained, namely the negative or close to zero δR values, suggest that the reduced offset between atmospheric and surface water 14C content is due to the existence of a strong stratification of the water column and environmental factors in the Galician rías during the Iron Age and the Medieval period.
Radiocarbon Marine Reservoir Ages in the Northwestern Pacific Off Hokkaido Island, Japan, During the Last Deglacial Period
Authors: Ohkushi Ken'ichi , Uchida Masao , Aoki Kaori , Yoneda Minoru , Ikehara Ken , Minoshima Kayo , Kawahata Hodaka , Tada Ryuji , Murayama Masafumi , Shibata Yasuyuki
Published: July 2016

We measured radiocarbon ages of planktic foraminifera in 4 sediment cores from the northwestern Pacific region off northern Japan in order to estimate marine reservoir ages during the B⊘lling-Aller⊘d period. The ages of deglacial tephra markers from 2 Japanese source volcanoes identified in these sediment cores had been previously estimated from 14C ages of terrestrial charcoal and buried forests. By comparing the foraminiferal and tephra ages, we estimated the surface water reservoir age during the B⊘lling-Aller⊘d period to be ∼1000 yr or more in the region off northern Japan. The deglacial reservoir ages were more than 200 yr higher than the Holocene values of ∼800 yr. The older deglacial ages may have been caused by active upwelling of deep water during the last deglaciation and the consequent mixing of “older” deep water with “younger” surface waters.
14C Groundwater Age and the Importance of Chemical Fluxes Across Aquifer Boundaries in Confined Cretaceous Aquifers of North Carolina, USA
Authors: Kennedy Casey D , Genereux David P
Published: July 2016

Radiocarbon activity, He concentrations, and other geochemical parameters were measured in groundwater from the confined Black Creek (BC) and Upper Cape Fear (UCF) aquifers in the Coastal Plain of North Carolina.14C ages adjusted for geochemical and diffusion effects ranged from 400 to 21,900 BP in the BC, and 13,400 to 26,000 BP in the underlying UCF; ages increased coastward in both aquifers. Long-term average linear groundwater velocity is about 2.5 m/yr for the BC, and somewhat larger for the UCF. Aquifer-aquitard exchange is an important influence on the DIC concentration,14C activity, and estimated age of aquifer groundwater. Accounting for this exchange in14C age calculations places the groundwater samples with the lowest estimated recharge temperatures nearest in time to the last glacial maximum. Traditional geochemical correction models that do not account for aquifer-aquitard exchange significantly overestimate groundwater age. He concentration in groundwater varies with both age and stratigraphic position. Dissolved He data provide strong evidence of upward vertical He transport through the study aquifers; data from the UCF are broadly consistent with the pattern expected for a confined aquifer receiving a concentrated, localized He flux from below (based on a previously published model for this situation), in this case most likely from crystalline bedrock. He has potential as an indicator of groundwater age in the study aquifers, if interpreted within an appropriate analytical framework that includes the observed strong vertical transport. δ18O in the oldest groundwater is enriched (relative to modern groundwater) by 1 to 1.2‰, the opposite of the δ18O depletion found in many old groundwaters but consistent with the enrichment found in groundwater in this age range in Georgia and Florida.
Grant Kocharov
Authors: Dreschoff Gisela
Published: July 2016

Grant Kocharov was a man whose life mirrored all the complexity and controversy of the fate of Russia in the second part of the 20th century. Kocharov was a bright, colorful, and ambitious person. He was born in Georgia, and his childhood and youth were not sunny and cloudless. His father died early and it was very difficult for his mother to feed their large family.
A New Method for Analyzing 14C of Methane in Ancient Air Extracted from Glacial Ice
Authors: Petrenko Vasilii V , Smith Andrew M , Brailsford Gordon , Riedel Katja , Hua Quan , Lowe Dave , Severinghaus Jeffrey P , Levchenko Vladimir , Bromley Tony , Moss Rowena , Mühle Jens , Brook Edward J
Published: July 2016

We present a new method developed for measuring radiocarbon of methane (14CH4) in ancient air samples extracted from glacial ice and dating 11,000–15,000 calendar years before present. The small size (∼20 μg CH4 carbon), low CH4 concentrations ([CH4], 400–800 parts per billion [ppb]), high carbon monoxide concentrations ([CO]), and low 14C activity of the samples created unusually high risks of contamination by extraneous carbon. Up to 2500 ppb CO in the air samples was quantitatively removed using the Sofnocat reagent. 14C procedural blanks were greatly reduced through the construction of a new CH4 conversion line utilizing platinized quartz wool for CH4 combustion and the use of an ultra-high-purity iron catalyst for graphitization. The amount and 14C activity of extraneous carbon added in the new CH4 conversion line were determined to be 0.23 ± 0.16 μg and 23.57 ± 16.22 pMC, respectively. The amount of modern (100 pMC) carbon added during the graphitization step has been reduced to 0.03 μg. The overall procedural blank for all stages of sample handling was 0.75 ± 0.38 pMC for ∼20-μg, 14C-free air samples with [CH4] of 500 ppb. Duration of the graphitization reactions for small (<25 μg C) samples was greatly reduced and reaction yields improved through more efficient water vapor trapping and the use of a new iron catalyst with higher surface area. 14C corrections for each step of sample handling have been determined. The resulting overall 14CH4 uncertainties for the ancient air samples are ∼1.0 pMC.
First Reported Samples from the Radiocarbon Laboratory of the University of Tennessee Center for Archaeometry and Geochronology: Dates from the Mccrosky Island Archaeological Site (40SV43), Sevier County, Tennessee, USA
Authors: Weinand Daniel C , Polhemus Richard R , Blankenship Sarah A , Simek Jan F
Published: July 2016

This study presents the results of archaeological samples submitted for dating at the recently constructed University of Tennessee Center for Archaeometry and Geochronology (UTCAG) radiocarbon dating laboratory (Knoxville, Tennessee, USA). The samples selected for this initial study were obtained from excavations at the McCrosky Island site (40SV43) in Sevier County, Tennessee, USA. Three of the samples dated were split between the UTCAG laboratory and another laboratory to assess the UTCAG laboratory protocols. In an effort to further validate the laboratory methods employed, several other samples were submitted without prior knowledge of contextual data. The dates obtained for these samples were then compared to their association with recovered artifacts and/or archaeological context.
Radiocarbon Content of Tropospheric CO2at China Lake, California 1977–1983
Authors: Berger Rainer , Jackson T B , Michael Robert , Suess H E
Published: July 2016

The measurements reported here are a continuation of tropospheric radiocarbon measurements in carbon dioxide carried out since 1961 at our China Lake, California collection facility. The data show a continued decrease in radiocarbon activity from ca 330‰ in 1977 to 215‰ in 1983 in agreement with similar analyses in Europe for the same time interval.
Study of Bone Radiocarbon Dating Accuracy at the University of Arizona NSF Accelerator Facility for Radioisotope Analysis
Authors: Stafford Thomas W , Jull A J T , Brendel Klaus , Duhamel Raymond C , Donahue Douglas
Published: July 2016

Bone would seem to be an ideal material for14C dating because this calcified tissue contains 20 weight per cent protein. Fossil bone, however, can lose most of its original organic matter and frequently contains contaminants having different14C ages. Numerous14C dates on bone have been available to archaeologists and geologists but many age determinations have been inaccurate despite over 30 years of research in the field following the first14C age determinations on bone (Arnold & Libby, 1951). This situation remained unchanged until simple pretreatments were abandoned and more bone-specific fractions were isolated. The ideal solution is to use accelerator mass spectrometer14C dating, which facilitates the use of milligram-sized amounts of highly purified compounds—an approach impossible to pursue using conventional14C decay-counting methods.
Rudjer Bošković Institute Radiocarbon Measurements IX
Authors: Srdoč Dušan , Horvatinčić Nada , Obelić Bogomil , Bronić Ines Krajcar , Sliepčević Adela
Published: July 2016

The following radiocarbon date list contains dates of samples from Plitvice Lakes measured since our previous list dealing with tufa from this region (Srdoč et al, 1982). Tufa measurements from the Knin area in S Croatia and some localities in Bosnia are also listed. Age calculations are based on the Libby half-life (5570 ± 30) yr and reported in years before 1950. Reported ages are based on the initial activity of 85% except for lake sediments where calculations of initial activity have been performed. The modern standard is 0.95 of the NBS oxalic acid activity. Sample pretreatment and counting technique are essentially the same as described in R, 1971, v 13, p 135–140, supplemented by new techniques for groundwater processing (R, 1979, v 21, p 131–137). Statistical processing of data has been computerized (Obelić & Planinić, 1977; Obelić, 1980). The errors quoted correspond to 1 σ variation of sample net counting rate and do not include the uncertainty in 14C half-life.
Discussion Comments on Multiple Dating of a Long Flowstone Profile
Authors: Grün Rainer , Schwarcz Henry P
Published: July 2016

We strongly welcome the investigation by Geyh and Hennig (1986) and agree with their conclusion that the boundaries of the interglacial periods cannot be determined exactly using the methods applied so far in the Heggen cave. However, since we have been engaged for several years in the application of these methods (except 14C), and since the paper gives a very different interpretation of the ESR results from that presented by one of us (Grün, 1985), we feel the need to make some comments on this paper.
Growth Rates of Natural Amazonian Forest Trees Based on Radiocarbon Measurements
Authors: Mozeto A A , Fritz Peter , Moreira M Z , Vetter E , Aravena Ramon , Salati Eneas , Drimmie R J
Published: July 2016

Evergreen trees in the tropical rain forest of the Amazonas Basin can produce growth rings which are not necessarily related to annual events. Therefore, estimation of growth rate cannot be done by dendrochronology. This report presents a technique for determining the growth rate of these trees based on radiocarbon measurements of two segments of equal radial distance from the outer part of the tree trunk. The measured 14C activity is compared to local 14C fallout and growth rates are derived from models taking into account bomb 14C effects. Eleven trees from various parts of the Amazon Basin were analyzed. The average growth rates range from ca 5 to > 40 yr per centimeter corresponding to extrapolated ages from ca 60 to > 400 yr.
Hiroshima University Radiocarbon Dates I West and South Coasts of Sri Lanka
Authors: Katupotha Jinadasa
Published: July 2016

The following list reports radiocarbon dates of geologic samples collected from the west, southwest and south coasts of Sri Lanka during August 1985. The tidal range on Sri Lanka coasts is very small, the lowest neap at − 0.48m and highest spring at + 0.52m from msl (data based on the standard point of Colombo, datum level 0.38m below msl).
The Second International Symposium on Archaeology and 14C
Authors: Kra Renee
Published: July 2016

The Second International Symposium on Archaeology and 14C, September 7–11, 1987, Groningen, The Netherlands was a most successful forum for the exchange of information and ideas among archaeologists and radiocarbon daters. The sincere intent of the organizers to achieve closer understanding and appreciation between the two disciplines was apparent throughout the conference. Indeed, even the conference title was changed from “14C and Archaeology” to “Archaeology and 14C.”
Treatment of Discrepancies in Radiocarbon Dating
Authors: Vincent C H
Published: July 2016

A method is given for modifying the estimated radiocarbon dates of two samples when they are known to be in the wrong order.
La Plata Radiocarbon Laboratory Liquid Scintillation Counting and Inter-Laboratory Check Samples
Authors: Huarte Roberto Andres , Figini Anibal Juan
Published: July 2016

The development and improvement of benzene synthesis for radiocarbon dating by liquid scintillation counting was started at LATYR in 1981. The basic technique employed was described by Polach, Gower & Frazer (1972). The line of benzene synthesis is similar to that used by Coleman et al (1972). The pretreatment of the samples and transformation to CO2 has been previously described (Figini et al, 1984). The conditions of measurement were partially determined according to Pearson (1979). Results of measurements of interlaboratory check samples using the technique described are given.
Radiocarbon Data Base: Q&A—An Artificial Intelligence Data File Management Program
Authors: Kalin Robert M , Long Austin
Published: July 2016

The “C14” data base, designed and implemented at the University of Arizona Radiocarbon Dating Laboratory, uses Q&A, an artificial intelligence data file management program. The data entered into this data base are easily retrievable and exportable for submission to RADIOCARBON, and to the International Radiocarbon Data Base (IRDB). The use of artificial intelligence allows both novice and experienced computer operators to search and retrieve data with few key strokes and normal English sentences.
A Radiocarbon Sequence from the Toaga Site, Ofu Island, American Samoa
Authors: Kirch P V , Hunt T L , Tyler Jason
Published: July 2016

The Samoan Archipelago occupies a critical position for understanding the dispersal of early Austronesian-speaking peoples into the southwestern Pacific, including the initial colonization by humans of the Polynesian triangle. To date, the most easterly reported site of the Lapita cultural complex (Green, 1979; Kirch, 1984; Kirch & Hunt, 1988) is the Mulifanua site on Upolu Island, Western Samoa (Green & Davidson, 1974). Lapita colonists settled the larger, western Samoan Islands by the end of the second millennium bc. Archaeologic and linguistic evidence also suggest that the islands of Eastern Polynesia (eg, Marquesas, Society and Cook Islands) were settled, at least in part, from Samoa. However, the timing of this movement into Eastern Polynesia has not yet been dated to earlier than ca 150 bc on the basis of radiocarbon dating of cultural materials from the Marquesas Islands (Kirch, 1986; Ottino, 1985). This has raised the issue of whether there was a “long pause” between the settlement of Samoa (and the other islands of Western Polynesia, such as Tonga, Futuna, and ‘Uvea) and that of Eastern Polynesia (Irwin, 1981; Kirch, 1986; Terrell, 1986).
British Museum Natural Radiocarbon Measurements XXI
Authors: Ambers Janet , Matthews Keith , Bowman Sheridan
Published: July 2016

The following list consists of dates obtained by liquid scintillation counting of benzene for archaeologic samples mostly measured between June 1986 and June 1987.
Radiocarbon Dates of Riga I
Authors: Veksler V S
Published: July 2016

The Riga Radiocarbon Laboratory began its serial measurements in 1971. Radiocarbon activity is measured by solution scintillation counters. Benzol, obtained by acetylene trimerization on vanadium pentoxide activated silicagel, is used as 14C activity carrier. The dates refer to 1950 according to the 5568-year half-life of 14C. The statistical error is 1σ (Veksler, Putans & Savvaitov, 1971).

We present data here of samples from coastal regions of the USSR, which reflect their geologic-geomorphologic development (Veksler et al, 1975; Veksler, Putans & Stelle, 1977; Veksler & Prede, 1986).
Radiocarbon Dates of Riga II
Authors: Veksler V S
Published: July 2016

Our standard procedure of 14C concentration measurements is reported in Riga I. We report here data on samples from the Latvian SSR and Eastern Siberia.
UCLA Radiocarbon Dates XI
Authors: Berger Rainer , Protsch Reiner
Published: July 2016

The radiocarbon dates reported in this list are almost all based on collagen measurements from human archaeologic bone material. This collagen was isolated according to the methods developed by Berger, Horney and Libby (1964), Ho, Marcus and Berger (1969), Longin (1971) and Protsch (1973). All samples were counted as CO2gas at close to 1 atm in a 7.5L proportional counter with three energy channels. The14C dates reported are calculated with the Libby half-life of 5568 ± 30 years as required by convention.13C measurements were used to normalize to −25‰ in the standard manner. The biospheric standard is 95% the count rate of NBS oxalic acid for radiocarbon laboratories. Background is based on CO2obtained from marble. The accuracy of counter operation is checked against historically dated wood from the funerary boat of Sesostris III, 1872−8+4bc (Hayes, 1962). The14C ages are not tree-ring calibrated.
Rudjer Bošković Institute Radiocarbon Measurements XI
Authors: Srdoč Dušan , Obelić Bogomil , Horvatinčić Nada , Bronić Ines Krajcar , Sliepčević Adela
Published: July 2016

This is a list of radiocarbon analyses determined since our previous list (R, 1987, v 29, no. 1, p 135–147). As before, with the exception of speleothems and groundwaters, the calculations follow conventional radiocarbon protocol (Stuiver & Polach, 1977). Sample pretreatment, combustion and counting techniques are essentially the same as described in R, 1971, v 13, no. 1, p 135–140, supplemented by new techniques for groundwater processing (R, 1979, v 21, no. 1, p 131–137). Speleothem and groundwater model ages (given in the comment section of each listing) are based on an initial activity of 85 ± 10 percent modern carbon (pMC), as recommended in Srdoč et al (1986), without adjustment for δ13C. These model ages can be converted from the 5570-yr half-life to the chronometrically more correct half-life of 5730 yr by multiplying by the factor 1.029. The “± figures” on these model ages are statistical combinations of the 1σ counting uncertainty and the ± 10% uncertainty in the assumed 85 pMC. Ages and “± figures” of all other samples are adjusted for stable isotope fractionation according to the recommendations in Stuiver and Polach (1977). Data processing is done by computer (Obelić & Planinić, 1977; Obelić, 1980). Sample descriptions are prepared in collaboration with collectors and submitters.
Anomalous AMS Radiocarbon Ages for Foraminifera from High-Deposition-Rate Ocean Sediments
Authors: Broecker Wallace S , Trumbore Susan , Bonani Georges , Wölfli Willy , Klas Millie
Published: July 2016

Radiocarbon ages on handpicked foraminifera from deep-sea cores are revealing that areas of rapid sediment accumulation are in some cases subject to hiatuses, reworking and perhaps secondary calcite deposition. We present here an extreme example of the impacts of such disturbances. The message is that if precise chronologies or meaningful benthic planktic age differences are to be obtained, then it is essential to document the reliability of radiocarbon ages by making both comparisons between coexisting species of planktonic foraminifera and detailed down-core sequences of measurements.
Temporal 10Be and 14C Variations: A Tool for Paleomagnetic Research
Authors: Kocharov G E , Blinov A V , Konstantinov A N , Levchenko V A
Published: July 2016

Temporal variations of cosmogenic radionuclide atmospheric concentrations can be caused by such global phenomena as solar activity and geomagnetic field changes as well as atmospheric circulation processes. These causes can be distinguished by the comparison of several isotope records corresponding to the same time period. We discuss a possibility for reconstructing the geomagnetic moment during the last 30,000 years from the comparison of 10Be and 14C concentrations in terrestrial archives. The results agree with conventional paleomagnetic data and promise to enrich our knowledge of geomagnetic field variations and reversals.
Islands of Affluence in a Sea of Despair
Authors: Kra Renee
Published: July 2016

I recently had the privilege of attending the Conference on Technology-Based Confidence Building: Energy & Environment, hosted by Los Alamos National Laboratory and The University of California, in Santa Fe, New Mexico, July 9–14, 1989.
Radiocarbon Results from the Iron IIA Site of Atar Haroa in the Negev Highlands and their Archaeological and Historical Implications
Authors: Boaretto Elisabetta , Finkelstein Israel , Shahack-Gross Ruth
Published: July 2016

In this article, we present a set of radiocarbon measurements from Atar Haroa, a site that belongs to the early Iron IIA Negev Highlands settlement system in southern Israel. The results place activity at the site in the 9th century BCE, with a possibility that it was founded in the 10th century BCE, probably in the second half. The Atar Haroa measurements seem to indicate that the early Iron IIA phase in the ceramic typology of Israel lasted until the mid-9th century BCE—somewhat later than previously suggested. These new data shed light on several issues related to the history of southern Israel in the late 10th and 9th centuries BCE.
Current Pretreatment Methods for AMS Radiocarbon Dating at the Oxford Radiocarbon Accelerator Unit (Orau)
Authors: Brock Fiona , Higham Thomas , Ditchfield Peter , Ramsey Christopher Bronk
Published: July 2016

In this paper, we summarize the main chemical pretreatment protocols currently used for AMS radiocarbon dating at the Oxford Radiocarbon Accelerator Unit, updating the protocols last described by Hedges et al. (1989).
Measuring Submicron-Size Fractionated Particulate Matter on Aluminum Impactor Disks
Authors: Buchholz Bruce A , Zermeño Paula , Hwang Hyun-Min , Young Thomas M , Guilderson Thomas P
Published: July 2016

Submicron-sized airborne particulate matter (PM) is not collected well on regular quartz or glass fiber filter papers. We used a micro-orifice uniform deposit impactor (MOUDI) to fractionate PM into 6 size fractions and deposit it on specially designed high-purity thin aluminum disks. The MOUDI separated PM into fractions 56–100, 100–180, 180–320, 320–560, 560–1000, and 1000–1800 nm. Since the MOUDI has a low flow rate (30 L/min), it takes several days to collect sufficient carbon on 47-mm foil disks. The small carbon mass (20–200 μg C) and large aluminum substrate (∼25 mg Al) present several challenges to production of graphite targets for accelerator mass spectrometry (AMS) analysis. The Al foil consumes large amounts of oxygen as it is heated and tends to melt into quartz combustion tubes, causing gas leaks. We describe sample processing techniques to reliably produce graphitic targets for 14C AMS analysis of PM deposited on Al impact foils.
14C Ages of Bone Fractions from Armenian Prehistoric Sites
Authors: Cherkinsky Alexander , Chataigner Christine
Published: July 2016

Prehistoric cultures in Armenia are still poorly known; thus, accelerator mass spectrometry (AMS) radiocarbon dates are invaluable in constructing an accurate chronology. Bone samples have been collected from sites representing the Middle Paleolithic, Chalcolithic, and Early Bronze periods. Most of the bone samples are poorly preserved. We describe the separation technique for the extraction of both the bioapatite and collagen fractions. In many cases where the bone had very low organic material content, the collagen fractions yielded a younger age, although the ages of bioapatite fractions were found to be in good agreement with associated archaeological artifacts. In cases where bone was well preserved, both fractions exhibited ages in good agreement with the artifacts. The accuracy of 14C dating of bone material always depends on its degree of preservation, and each case should be carefully evaluated to determine which fraction is less contaminated in order to accurately date a burial event.
Paleodiet Reconstruction of Human Remains from the Archaeological Site of Natfieh, Northern Jordan
Authors: Al-Bashaireh Khaled , Al-Shorman Abdullah , Rose Jerome , Jull A J Timothy , Hodgins Gregory
Published: July 2016

This investigation concerns human teeth and bones from the site of Natfieh, north Jordan. Nitrogen and carbon isotope analyses were used to model the paleo-economy by reconstructing Natfieh's paleodiet during a specific time period.14C dating of human teeth and bones from the site of Natfieh, north Jordan, demonstrate that they belong to the Early Roman period and match the archaeological date from the tomb and grave goods typology. Stable isotope analyses of these humans have provided new information about the subsistence and society of individuals buried at Natfieh. Natfieh is today agriculturally productive and must have been so in antiquity with most of the foodstuffs having been produced locally. The long distance between Natfieh and the closest aquatic food source (Mediterranean Sea and Lake Tiberias) and the high cost of land transportation might be the reason for the low consumption of marine protein. The results agree with past research on the Roman diet showing that plants were the common source of food for the Romans and fish may have been restricted to elite members of the society.
Dietary Reconstruction of the Okhotsk Culture of Hokkaido, Japan, Based on Nitrogen Composition of Amino Acids: Implications for Correction of 14C Marine Reservoir Effects on Human Bones
Authors: Naito Yuichi I , Chikaraishi Yoshito , Ohkouchi Naohiko , Mukai Hitoshi , Shibata Yasuyuki , Honch Noah V , Dodo Yukio , Ishida Hajime , Amano Tetsuya , Ono Hiroko , Yoneda Minoru
Published: July 2016

The relative contribution of marine-derived carbon in the ancient diet is essential for correcting the marine reservoir effect on the radiocarbon age of archaeological human remains. In this study, we evaluated the marine protein consumption of 3 human populations from the Okhotsk culture (about AD 550–1200) in Hokkaido, Japan, based on stable carbon and nitrogen isotopic compositions in bulk bone collagen as well as the nitrogen isotopic composition of glutamic acid and phenylalanine. Despite the similarity of carbon and nitrogen isotopic composition of bulk collagens, nitrogen isotopic composition of their constituent amino acids suggests differences in fur seal contributions among northern Hokkaido (0–24% for Kafukai 1, 0–10% for Hamanaka 2) and eastern Hokkaido (78–80% for Moyoro) populations. It suggests that nitrogen composition of glutamic acid and phenylalanine could provide a detailed picture of ancient human subsistence.
Fish Reservoir Effect on Charred Food Residue 14C Dates: Are Stable Isotope Analyses the Solution?
Authors: Boudin Mathieu , Strydonck Mark Van , Crombé Philippe , Clercq Wim De , van Dierendonck Robert M , Jongepier Hans , Ervynck Anton , Lentacker An
Published: July 2016

In order to verify the relative dating based on pot type morphology and decoration of the Swifterbant pottery collected at the Final Mesolithic site of Doel “Deurganckdok” (Belgium) and of the Late Iron Age pottery excavated at Grijpskerke (the Netherlands), direct radiocarbon dates were obtained on charred food residue preserved on the inner surface of numerous potsherds. In addition, a number of indirect 14C dates were obtained from samples of organic material. In the case of Doel, the results indicate an important incompatibility between the charred food residue dates and the other dates, the former being systematically older. This difference may be explained by a reservoir effect of the charred food residue, caused by the processing of (freshwater) fish. The 14C dates for the Grijpskerke site are in agreement between the charred food residue and the organic material. The stable isotopes of the charred food residue were analyzed to demonstrate fish processing in the pottery, but the results were inconclusive.
14C Age Measurements of Single-Year Tree Rings of Old Wood Samples 22,000 14C Years BP
Authors: Sato Taiichi , Sakurai Hirohisa , Suzuki Kayo , Takahashi Yui
Published: July 2016

Radiocarbon ages of single-year tree rings were measured for Kaminoyama wood samples using accelerator mass spectrometry (AMS) in 2 Japanese facilities, MALT and JAEA, in order to investigate the periodic variation of 14C concentrations relating to the 11-yr solar cycle near 26,000 yr BP. Eight sequential measurements of 14C ages were carried out for a set of 13 alternate single-year tree rings covering 26 yr. Averages of the 5 data sets in MALT and 3 data sets in JAEA were 22,146 ± 50 and 22,407 ± 58 14C yr BP, respectively, indicating an offset of 260 ± 77 14C yr. Multiple sequential measurements are advantageous for evaluating offsets. The standard deviation of the residuals of 14C ages from the averages in each data set was 118 14C yr, in contrast to that of 234 14C yr for the combined data sets due to an elimination effect in the offsets. The profiles of weighted mean values for the residuals of 14C ages showed similar enhancements with a width of ∼12 yr for measurements in the 2 facilities. This indicates the reproducibility of the multiple sequential measurements. In the profile for the combined 8 data sets, the 14C enhancement was 73 ± 36 14C yr from the average.
Paleoearthquakes as Anchor Points in Bayesian Radiocarbon Deposition Models: A Case Study from the Dead Sea
Authors: Kagan Elisa J , Stein Mordechai , Agnon Amotz , Ramsey Christopher Bronk
Published: July 2016

The Bayesian statistical method of the OxCal v 4.1 program is used to construct an age-depth model for a set of accelerator mass spectrometry (AMS) radiocarbon ages of organic debris collected from a late Holocene Dead Sea stratigraphic section (the Ein Feshkha Nature Reserve). The model is tested for a case where no prior earthquake information is applied and for a case where there is incorporation of known ages of 4 prominent historical earthquakes as chronological anchor points along the section. While the anchor-based model provided a tightly constrained age-depth regression, the “non-anchored” model still produces a correlation where most of the 68% or 95% age ranges of the 52 seismites can be correlated to historical earthquakes. This presents us with the opportunity for high-resolution paleoseismic analysis and comparison between various sites.
Spatial Distribution of Δ14C Values of Organic Matter in Surface Sediments Off Saru River in Northern Japan, One Year After a Flood Event in 2006
Authors: Nagao Seiya , Irino Tomohisa , Aramaki Takafumi , Ikehara Ken , Katayama Hajime , Otosaka Shigeyoshi , Uchida Masao , Shibata Yasuyuki
Published: July 2016

Dispersion and deposition of terrestrial organic matter by flooding on the inner shelf were studied using C/N ratios, δ13C, and Δ14C values of sedimentary organic matter. Surface sediment samples (top 2 cm) were collected from coastal areas near the Saru River in southwestern Hokkaido, northern Japan, 1 yr after a flood event in 2006. Riverine suspended solids were also collected at a fixed station downstream during 2006–2008. Sandy sediments were located at the front of the river mouth and the western part of the sampling area, with the δ13C of organic matter ranging from −23.8‰ to −22.0‰, Δ14C of –655‰ to –388‰, and an organic carbon/total nitrogen (C/N) ratio of 5.9–7.7. On the other hand, silt and clay sediments were distributed in a restricted area 11–16 km from the river mouth, with lighter δ13C (–26.7‰ to −24.1‰) and higher Δ14C (–240‰ to –77‰) of organic matter and C/N ratio (7.8–13.3). From end-member analysis, the apparently younger and less degraded organic matter in the silt and clay sediments consists mainly of terrestrial organic matter released by flood events. They remain in the depression, although most flood deposits were moved to deep-sea environments.
Variability of Dissolved Inorganic Radiocarbon at a Surface Site in the Northeast Pacific Ocean
Authors: Druffel Ellen R M , Beaupré Steven , Griffin Sheila , Hwang Jeomshik
Published: July 2016

We report radiocarbon measurements of dissolved inorganic carbon (DIC) in surface water samples collected daily during 12 cruises to Station M in the northeast Pacific off central California. Individual surface Δ14C values ranged from 22‰ to 70‰ over 10 yr. Variability of average cruise values is highest during winter likely due to increased mixing. A general decrease of Δ14C values was observed at a rate of about 3‰ per year between 1994 and 2004, about half of that in atmospheric CO2 during this period (Levin and Kromer 2004). The Δ14C results ranged from 2–18‰ during individual cruises and were often significantly larger than the total uncertainty for individual measurements (±3.9‰). This indicates that a single Δ14C result from a surface site is not sufficient to capture the true variability of Δ14C in the surface ocean.
Pre-Bomb Marine Reservoir Variability in the Kimberley Region, Western Australia
Authors: O'Connor Sue , Ulm Sean , Fallon Stewart J , Barham Anthony , Loch Ian
Published: July 2016

New ΔR values are presented for 10 known-age shells from the Kimberley region of northwest Australia. Previous estimates of ΔR for the Kimberley region are based on only 6 individual shell specimens with dates of live collection known only to within 50 yr (Bowman 1985a). Here, we describe the results of our recent attempts to constrain ΔR variability for this region by dating a suite of known-age pre-AD 1950 shell samples from the Australian Museum and Museum Victoria. A regional ΔR of 58 ± 1714C yr for open waters between Broome and Cape Leveque is recommended based on 7 of these specimens. The criteria used to select shells for dating and inclusion in the regional mean are discussed.