Interactions between islands, ocean currents, and winds cause large-scale eddies and upwelling in the lee of islands that can result in spatial variation in the marine radiocarbon reservoir. For waters around New Ireland and the Bismarck Sea, ΔR values ranging from 365 to −320 14C yr have been reported (Kirch 2001; Petchey et al. 2004). Petchey et al. (2004) proposed that some of this variation was caused by seasonal reversals in the South Equatorial Current and North Equatorial Counter Current system, combined with Ekman upwelling from the Equator. McGregor et al. (2008) suggested additional complexity within this region caused by a change in the reservoir value over time in response to changing climatic conditions. We present a series of 14 new and extant published ΔR and R values on historic shells, combined with 8 values from archaeological terrestrial/marine pairs and U-Th dated coral, that support observations of localized variability caused by a complex interplay between seasonal currents, riverine input, and ocean eddies. On the basis of these values and oceanographic data, we divide the Bismarck Sea surface marine 14C reservoir into 6 tentative subregions. In particular, our results support significant variation within channels at the southwest and southeast ends of New Britain and towards the equatorial boundary of the sea. Our results indicate that within the Bismarck Sea geographical variation appears to be more extreme than temporal over the last 3000 yr.

The basic chronology of Inca imperial expansion in Andean South America derives from historical accounts from the Spanish Colonial era, but several issues with this traditional chronology have arisen in recent decades. Advances in radiocarbon dating and calibration now give us some ability to refine or rebuild the chronology, and guidelines for obtaining the most useful dates are discussed. Dates recently obtained from the site of Chamical in the southern highlands of Ecuador are evaluated according to those guidelines, and they suggest Inca expansion to the north began 1 to 2 decades earlier than allowed in the traditional chronology. The chronology of Inca expansion presented in the Spanish chronicles is called into question by these and other dates, and by a reconsideration of the nature of sources of Inca history utilized by Spanish writers. Evidence suggests a primary Inca form of recording provincial conquests resulted in lists that were ordered geographically. However, those records were interpreted by colonial writers as being chronologically ordered, which led to written histories of Inca expansion that are not consistent with the actual historical sequence of events. As a result, the preferred approach to building a chronology of Inca expansion should be based on 14C dates, with historical sources used to supplement rather than structure the timeline.

Anomalous dates prior to 1000 yr BP have been reported for near-surface site deposits at Puapua'a in the dry and rocky zone of leeward (west) Hawai'i Island, compared to archipelago-wide earliest cultural layers generally in buried contexts 1000–800 yr BP. Redating and closer examination cannot validate these early dates in cultural association. In the thin sedimentary deposits, preserved cultural materials mostly postdate 600–400 yr BP, but some older materials were incorporated into the layer matrix. The results suggest a much shorter extant chronology of human settlement of this particular zone, whereas earliest sites most likely are preserved in different settings of the Hawaiian Islands.

By analyzing archaeological evidence and radiocarbon dates, we studied the Neolithization of Far Northeast Europe (Russian Perm' region, Komi Republic, and Nenets autonomous district). Our study shows that this process in the eastern European forest zone was rather ambiguous. Taking into account the periodicity of settling and short duration of residence here, the term “Neolithization” in its traditional sense cannot be applied to some territories in this region. For instance, the emergence of ceramics—the most important feature of Neolithization here—did not affect considerably the way of life of the ancient population, which continued the traditions of the Mesolithic hunter-gatherers well into the Early Neolithic. Such attributes as heat treatment of clay paste and siliceous rocks for changing physical features of natural materials, bifacial knapping, and construction of subterranean dwellings represent the archaeological evidence of Neolithization in the region.

A compilation of direct age determinations for Late Pleistocene human fossils in eastern Europe and Asia is presented in this paper, and current problems with the dating of hominids in these regions are discussed. Only 25 human finds (4 Neanderthals and 21 modern humans) have been directly dated from Pleistocene eastern Europe and Asia. Indirect dating of human remains (using presumably associated organics) often is insecure, especially when information about the exact provenance of human fossils is lacking. Continuation of direct dating of Late Pleistocene humans in Eurasia, primarily with the help of the accelerator mass spectrometry (AMS) 14C method, is therefore an urgent task.

We present the results of accelerator mass spectrometry (AMS) radiocarbon dating of 11 samples collected from 4 locations in southern Iraq. As a result of the hiatus in fieldwork in that region since 1990, and the antiquity of the majority of archaeological excavations conducted there, the record of 14C dates for southern Mesopotamia is patchy for all periods. This is especially true for the mid-Holocene, when the world's oldest and longest-sustained urban system first emerged there. The dates here reported not only make a significant contribution to available dates for this important region and period; they fill specific gaps in crucial geographic coverage, and shed light on the extent of marshland boundaries and the antiquity of settlement at key urban centers.

The East Texas Radiocarbon Database contributes to an analysis of tempo and place for Woodland era (∼500 BC–AD 800) archaeological sites within the region. The temporal and spatial distributions of calibrated 14C ages (n = 127) with a standard deviation (ΔT) of 61 from archaeological sites with Woodland components (n = 51) are useful in exploring the development and geographical continuity of the peoples in cast Texas, and lead to a refinement of our current chronological understanding of the period. While analysis of summed probability distributions (SPDs) produces less than significant findings due to sample size, they are used here to illustrate the method of date combination prior to the production of site- and period-specific SPDs. Through the incorporation of this method, the number of 14C dates is reduced to 85 with a ΔT of 54. The resultant data set is then subjected to statistical analyses that conclude with the separation of the east Texas Woodland period into the Early Woodland (∼500 BC–AD 0), Middle Woodland (∼AD 0–400), and Late Woodland (∼AD 400–800) periods.

Two soil profiles from northeast India, one from Bakrihawar, an agricultural land, and the other from Chandipur, a virgin hilly area from Assam, are investigated to understand the organic carbon dynamics of the area. Due to frequent flooding, the Bakrihawar soil has accumulated a higher clay content than that of Chandipur. The carbon content is less than 1% by weight in both the sites. The higher clay content is responsible for relatively more soil organic carbon at Bakrihawar. The mean δ13C values at both sites reflect the values of the overlying vegetation. At Bakrihawar, both rice cultivation (C3) and natural C4 grasses contribute to higher mean enriched values of 13C relative to Chandipur, where the surface vegetation is mostly of C3 type. The turnover time of organic carbon, estimated using the residual radiocarbon content, depends strongly on the soil particle size distribution, especially the clay content (i.e. it increases with clay content). To the best of our knowledge, this is the first soil carbon dynamics study of its kind from northeast India.

Four late Pleistocene tephra layers—Tane I (Tn1), II (Tn2), III (Tn3), and IV (Tn4) in ascending order—are intercalated between widespread tephras, Kikai-Tozurahara (K-Tz: 95 ka) and Aira-Tn (AT: 30 cal kBP), on Tanegashima Island, in southern Japan. Paleolithic ruins such as the Yokomine C and Tatikiri archaeological sites were excavated from the loam layer between the Tn4 and Tn3 tephras. To refine the chronological framework on the island, we conducted accelerator mass spectrometry (AMS) radiocarbon dating for 2 paleosol and 6 charcoal samples related with the late Pleistocene tephras and the Yokomine C archaeological site. The obtained 14C dates are consistent with the stratigraphy in calendar years, 33 cal kBP for Tn4, 40 cal kBP for Tn3, and >50 cal kBP for Tn2 and Tn1. The charcoal dates from Yokomine C, 32–38 cal kBP, not only constrain the age of Tn4 and Tn3 ashes, but also serve as a possible date for the site. We also measured the major element compositions of volcanic glass shards with EDS-EPMA to characterize these tephras. Although we could not find a possible correlative for Tn3 and Tn4 ashes using major element oxides of the glass shards, i.e. 75–76 wt% in SiO2, the glass chemistry obtained in this study will be valuable in correlating these tephras with their source volcanoes in the near future.

This article presents an application of a fixed-energy balance counting window in radiocarbon dating of geological peat samples. We determine a fixed-energy balance counting window with an inexpensive liquid scintillation counting ICELS system. We show long-term modern biosphere standard records that show stability sufficient for dating samples up to approximately 30,000 14C yr BP. We then compare our results to ones obtained previously using a Quantulus 1220™.

The oasis of Samarkand in the Middle Zeravshan Valley (modern Uzbekistan) was a major political and economic center in ancient western Central Asia. The chronology of its irrigation system was, until now, only constrained by the quality and quantity of archaeological findings and several different hypotheses have been proposed for it. We use a new approach combining archaeological surveying, radiocarbon dating, sedimentary analysis, and the numerical modeling of a flood event to offer new evidence for, and quantitative dating of, the development of irrigation system on the southern flank of the Middle Zeravshan Valley. We analyzed 13 bones and charcoals from 3 archaeological sites and obtained new 14C ages from Afrasiab (ancient Samarkand), a dwelling damaged by flooding in the 2nd century AD (site code: SAM-174) and the fortress of Kafir Kala. We established the origin of sedimentary deposits at the sites to infer the presence of the 2 most important canals of the southern flank: the Dargom and the Yanghiaryk. Finally, we show with a numerical model of overland flow that a natural flood was unlikely to have produced the damage observed at SAM-174. The combined results of the study indicate that the canals south of Samarkand existed, and were mainly developed, in the 2nd century AD and were not connected to the main feeding canal of Afrasiab at that time.

During the Last Glacial Maximum (LGM) about 25,000 yr ago, the area of what is now New York State (USA) was almost entirely covered by the Laurentide Ice Sheet (LIS; Dyke et al. 2002). Subsequent habitation of this area after the melting of the LIS necessitates dispersal of fauna, and the timing of the dispersal of particular species may aid in the understanding of how the modern ecosystems of New York were assembled. Mastodons and mammoths represent the most abundant post-LGM Pleistocene megafauna recovered in New York. However, many of the specimens have not been dated. This paper presents a set of dates from bone and tooth dentine collagen of late Pleistocene mastodon (n = 7) and mammoth (n = 3) specimens housed in the Vertebrate Paleontology Collections at the New York State Museum, Albany, New York, USA.

During the past 30 yr, the biblical narrative relating to the establishment of a kingdom in Judah has been much debated. Were David and Solomon historical rulers of an urbanized state-level society in the early 10th century BC, or was this level of social development reached only at the end of the 8th century BC, 300 yr later? Recent excavations at Khirbet Qeiyafa, the first early Judean city to be dated by radiocarbon, clearly indicate a well-planned, fortified city in Judah as early as the late 11th to early 10th centuries BC. This new data has far-reaching implications for archaeology, history, and biblical studies.

The reliability of a radiocarbon date depends in part on the degree of precision and accuracy of the measurement. While analytical precision and accuracy can be improved by careful sample cleaning procedures and high laboratory standards, accuracy also depends upon the certainty to which the sample can be attributed to a specific material culture or event in the past. This might be questionable when based only on partial archaeological information. As a consequence, it is very difficult to date clear-cut chronological transitions within specific periods. This issue is particularly apparent in the case of Mediterranean Iron Age chronology, where 2 somewhat different perspectives are proposed, the “High Chronology” and the “Low Chronology,” which differ by ∼50 yr. Here, we present the preliminary results of an ongoing project that aims to characterize Iron Age archaeological contexts from the eastern Mediterranean, and to identify those contexts that are suitable for dating, in order to improve the accuracy of 14C dates. This study involves the analysis of sediments by means of FTIR spectrometry, soil micromorphology, phytolith and phosphate extraction, all of which provide insights into the site-formation and postdepositional processes at the different sites under investigation. These techniques, applied at Tell es-Safi/Gath (Israel), enabled us to better identify a secure context for dating.

Single- and multiphase models have been used extensively in construction of chronologies. We model more gradual transition between phases with a trapezoid model since it better reflects the nature of the information that goes into the model prior. We find that a simple trapezoid model has a bias that docs not reflect prior knowledge, and thus propose an addition of a noninformative clement to the prior. We also present an alternative parameterization, which transforms the current abrupt transition model into a model that allows for gradual changes. The addition of a noninformative prior ensures model flexibility. We evaluate these Bayesian models using 2 case studies.

New attempts arc presented to determine the age of large Pleistocene mammals excavated at Starunia, ∼130 km southeast of Lviv, Ukraine. This remarkable discovery made at the beginning of the 20th century included a complete carcass of woolly rhinoceros (No. 2), fragments of 3 woolly rhinoceroses (Nos. 1, 3, and 4) and remnants of numerous specimens of other fossil fauna and flora. Although attempts to date paleontological findings from Starunia site go back to the early 1970s, the results obtained before 2006 arc somewhat misleading, mostly due to unresolved contamination problems. Comprehensive cleaning of the samples adopted in the framework of this study was aimed at removal of 2 potential sources of contamination: (i) radiocarbon-free hydrocarbons abundant at the burial site; and (ii) allochthonous organic materials containing contemporary carbon that were used in the past during preservation of the dated specimens. Two types of samples have been analyzed for their 14C content in the framework of the present study: (i) fragments of bones and teeth collected from specimens stored or exposed in the Natural History museums in Lviv and Kraków; and (ii) samples of terrestrial macrofossils retrieved from sediment cores obtained during the 2007–2008 field campaigns in the Starunia area. 14C analyses of collagen were supplemented by measurements of its elemental C/N ratio and 13C/12C and 15N/14N isotope ratios. Three 14C dates obtained for rhinoceros No. 2 span the age range from 35.3 to 40.0 ka BP, in agreement with the minimum age estimated from macrofossils. The mean value of 37.7 ± 1.7 ka BP falls in the range of ages reported for big Pleistocene mammals from other locations in Europe. The bones of rhinoceros No. 3, which were found in close vicinity to those of rhinoceros No. 2, reveal a 14C age of 36.7 ± 0.6 ka BP. The δ15N and δ13C values obtained for collagen extracted from bones and teeth belonging to rhinoceroses Nos. 1, 2, and 3 are in a broad agreement with analogous literature data for large Pleistocene mammals found in other sites in Europe, North America, and Siberia.

Traditional archaeological approaches in the central Negev Desert used to employ excavation techniques in post-prehistoric periods in which stratigraphy is based on architecture, while material culture forms the basis for dating assessment and chronology. Such an approach was understandable, as it focused on the most visible remains of past human habitation. However, the detailed habitation record is in the soil rather than in the walls. Moreover, ceramics and stone tools in desert cultures often have limited time resolution in terms of absolute chronology. The rural desert site of Horvat Haluqim in the central Negev yielded 2 habitation periods with the traditional methodology: (1) Roman period, 2nd–3rd centuries CE; (2) Iron Age IIA, 10th century BCE. We have conducted at Horvat Haluqim initial excavations in small building remains that were never excavated before. Our excavation methodology focuses on detailed examination of the archaeological soil in building structures, coupled with accelerator mass spectrometry (AMS) radiocarbon dating for chronology, and micromorphology of undisturbed soil samples to study stratigraphy and soil contents at the microscopic scale. Here, we report preliminary results, concentrating on the 14C dates. These suggest a much longer habitation history at the site during the Iron Age. The 14C dates obtained so far from these building remains cover Iron Age I, II, III, and the Persian period. The oldest calibrated date (charred C4 plants) in a rectangular building structure (L100) is 1129–971 BCE (60.5%, highest relative probability). The youngest calibrated date in a round building structure (L700) is 540–411 BCE (57.9%, highest relative probability). This excavation methodology provides additional “eyes” to look at past human habitation in the Negev Desert, seeing more periods and more detail than was possible with traditional schemes and ceramic dating.

This paper presents dating results of geological (speleothems, tufa, soil, and sediment), biological (mollusks and botanical), as well as hydrogeological samples from Croatia, Slovenia, Bosnia and Herzegovina, Turkey, and China. Included arc results of samples measured by gas proportional counting (GPC) in the Zagreb lab until abandonment of this technique in 2007, as well as results of several series measured by both GPC and liquid scintillation counting (LSC) methods.