General chronological frameworks created recently for the Neolithic complexes of China, Japan, Korea, and far eastern Russia allow us to reveal temporal patterns of Neolithization, origin of food production, and the emergence of civilizations. Pottery originated in East Asia, most probably independently in different parts of it, in the terminal Pleistocene, about 14,800–13,300 BP (uncalibrated), and this marks the beginning of the Neolithic. Agriculture in the eastern part of Asia emerged only in the Holocene. The earliest trace of millet cultivation in north China can now be placed at ∼9200 BP, and rice domestication in south China is dated to ∼8000 BP. Pottery in East Asia definitely preceded agriculture. The term “civilization,” which implies the presence of a state level of social organization and written language, has been misused by scholars who assert the existence of a very early “Yangtze River civilization” at about 6400–4200 cal BP. The earliest reliable evidence of writing in China is dated only to about 3900–3000 cal BP, and no “civilization” existed in East Asia prior to this time.

The following list contains dates of samples measured since our previous list (R, 1977, v 19, p 465-475). As before, age calculations are based on the Libby half-life, 5570 ± 30 years, and reported in years before 1950. The modern standard is 0.95 of the activity of NBS oxalic acid. Solid sample pretreatment, combustion and counting technique are essentially the same as described in R, 1971, v 13, p 135-140. Groundwater samples were prepared following the procedure adopted by the IAEA (IAEA, 1977). Carbonates and hydrocarbonates from water samples were precipitated by adding saturated barium chloride solution while the alkalinity was adjusted to pH = 8 by adding carbonate-free saturated solution of sodium hydroxide. The precipitation was enhanced by adding iron salts and Praestol as coagulating medium. Carbon dioxide was evolved by acidification of the precipitate and converted to methane. Statistical processing of data has been computerized (Obelić and Planinić, 1975). Sample descriptions were prepared with collectors and submitters. The errors quoted correspond to 1σ variation of sample net counting rate and do not include the uncertainty in 14C half-life.

Archaeological investigations at the Ritidian site in Guam provide a series of radiocarbon dates spanning the potential range of human presence in the region. Paired marine and terrestrial samples offer a basis for ΔR calculation, as well as evaluation of the utility of different types of marine samples for 14C dating of archaeological contexts. The results indicate an early period of temporary fishing camp activity in the context of higher sea level and little or no stable beach, followed by larger-scale residential activity in the context of lower sea level and an extensive stable beach landform.

Natural atmospheric 14C changes are caused by fluctuations in upper atmospheric 14C production rates (Q) that are related to earth geomagnetic field variations and changes in solar wind magnetic shielding properties. Climate variability may also be responsible for some of the changes because it influences exchange rates of 14C between the various terrestrial carbon reservoirs.

Upper atmospheric 14C production rates QM, in at/sec cm2 (earth), were calculated for the past 1200 years from the atmospheric 14C record and a carbon reservoir model. The changes in QM are compared in detail with the predicted Q variability derived from an Aa solar modulation mechanism and 20th century neutron flux observations. The influence of earth geomagnetic field changes on the magnitude of the solar wind modulation is discussed, and it is shown that the variations in this magnitude agree with the known differences in earth magnetic field intensity during the past 1200 years. The larger calculated QM oscillations during the sixth millennium bp also agree with this concept.

Solar wind magnetic as well as geomagnetic forces modulate the incoming cosmic ray flux and explain the main features of the atmospheric 14C record. It is argued that climatic fluctuation is not a dominant cause.

The oscillations between 3200 and 3700 BC, as measured by de Jong, Mook, and Becker, differ in rise time from those found for the current millennium.

I conducted a high-precision comparison at the 0.2% to 0.3% level with samples supplied by the radiocarbon laboratory of the Quaternary Research Center at the University of Washington (QRC). Four samples with ages ranging from modern to > 50,000 BP were dated in a blind test. The absence of cosmic-radiation background in AMS dating is a major advantage for dating samples > 35,000 BP. The reliability of AMS dates > 35,000 BP depends entirely on understanding the contamination processes. By comparing results with laboratories capable of sample enrichment, such as QRC, it is possible to identify and estimate the intrinsic 14C in the background samples as well as the contamination introduced by sample preparation.

We describe the design, construction, and testing of a new, simplified in situ radiocarbon extraction system at the University of Arizona. Blank levels for the new system are low ((234 ± 11) x 103 atoms (1 σ; n = 7)) and stable. The precision of a given measurement depends on the concentration of 14C, but is typically <5% for concentrations of 100 x 103 atoms g–1 or more. The new system is relatively small and easy to construct, costs significantly less than the original in situ14C extraction system at Arizona, and lends itself to future automation.

Samples from Tell es-Sultan, Jericho, were selected for high-precision 14C dating as a contribution toward the establishment of an independent radiocarbon chronology of Near Eastern archaeology. The material derives from archaeological excavations conducted by K. M. Kenyon in the 1950s. We present here the results of 18 samples, associated stratigraphically with the end of the Middle Bronze Age (MBA) at Tell es-Sultan. Six short-lived samples consist of charred cereal grains and 12 multiyear samples are composed of charcoal. The weighted average 14C date of the short-lived grains is 3306 ± 7 bp. The multiyear charcoal yielded, as expected, a somewhat older average: 3370 ± 6 bp. Both dates are more precise than the standard deviation (a) of the calibration curves and the absolute standard of oxalic acid. Calibration of the above Jericho dates is a bit premature, because several groups are currently testing the accuracy of both the 1986 and 1993 calibration curves. Nevertheless, preliminary calibration results are presented for comparison, based on 4 different calibration curves and 3 different computer programs. Wiggles in the calibration curves translate the precise bp dates into rather wide ranges in historical years. The final destruction of MBA Jericho occurred during the late 17th or the 16th century bc. More definite statements about the calibrated ages cannot be made until the accuracy of available calibration curves has been tested. Development of calibration curves for the Eastern Mediterranean region would be important.

We have performed a high-precision 14C wiggle-matching study on two oak beams from the “Castle of Amsterdam”. These beams are also dated by dendrochronology. Our two dating methods can only be made consistent using the recommended calibration curve (1986) instead of the revised one (1993).

Natural textiles provide suitable material for radiocarbon dating. Short-lived organic matter is usually involved and, if 14C dating is applied to pieces that are stylistically well dated, a better understanding of 14C dating of this type of material can be gained. This study presents some examples of dating that support the stylistic dates. Repeated analyses illustrate the robustness of the standard treatment applied to the textiles.

We developed and tested a new method to separate CO2 and CH4 from bulk gas samples for radiocarbon and stable-carbon analysis that utilizes a zeolite molecular sieve. To validate the technique, tests were performed using a suite of standard gases, composed of CO2 and CH4 of distinctly different isotopic composition. We employed the method to investigate the carbon isotopic composition of samples of dissolved CO2 and CH4 collected in situ from the near surface to deep layers of an ombrotrophic raised peat bog. Results showed that the age of both the CO2 and CH4 components of the dissolved gases increased with depth from ≃0–300 BP at 0.25 m to ≃4000 BP at 4 m. CH4 was mainly similar or slightly older in age compared to CO2, with the greatest difference in ages occurring at 1 m depth where CH4 was older by 430–615 yr. The δ13C values of CO2 increased with depth from −12.4‰ and −8.0‰ at 0.25 m to +6.9‰ and +8.3‰ at 4 m, whereas the δ13C of CH4 stayed in the range −58.4‰ to −70.6‰. The 14C results from the deepest layers are consistent with a similar source for both gases. 14C ages for the CO2 component were younger compared to CH4, within the shallower depths of the peat bog (≤1 m) and demonstrate the incorporation of acrotelm-derived respired CO2 into the catotelm.

We have determined the radiocarbon ages for 40-yr-interval tree rings in 2 fossil trees of the Towada Hachinohe buried forest, northeastern Honshu Island, Japan. The 14C ages range from 13.0 to 13.3 kyr BP (about 15.5 cal kyr BP). The weighted average of the 14C age of the outermost 5 rings is 13,133 ± 33 BP, which can be calibrated to 15,363–15,679 cal BP by using the IntCal04 standard curve (Reimer et al. 2004). The estimated δ14C values range between 265 and 300% and show approximately sinusoidal fluctuation of an indicated ∼200-yr cycle, perhaps reflecting contemporary solar activity change. Comparison between the tree 14C profile and the Cariaco Basin 14C record provides further information on the accurate date of the Towada Hachinohe buried forest and the eruption that produced it. 14C analysis of tree rings from the buried forest may contribute to the construction of a better 14C calibration curve and the elucidation of solar activity change during the last glacial period, as well as possible global and regional impacts of the huge eruption from Towada Volcano.

We present a method for the isolation of phenolic compounds derived from lignin for radiocarbon analysis. These phenols are generated by chemical oxidation of polymeric materials and derivatized for separation and recovery by preparative capillary gas chromatography (PCGC). This technique yields tens of micrograms of pure, stable compounds that can be converted to graphite and analyzed by accelerator mass spectrometry (AMS). Analysis of model flavor compounds and dated woods indicates that, in most cases, the radiocarbon (14C) contents of the individual compounds, corrected for the contribution of the derivative, agree with that of the bulk material to within 20%.

Modern bone contains ca 25% protein material, most of which is collagen. Amino acids separated from collagen isolated from bone are suitable for 14C dating of fossil bone, but attempts to carry out this procedure on bones seriously depleted in protein can yield erroneous 14C dates. Amino-acid analysis of fossil bone gives quantitative information on the degree of preservation of its organic component. Also, the relative abundance of the amino-acid components reveal the degree to which the collagen-like pattern has been altered. Alteration may be caused by addition of extraneous material. A 1mg sample of bone material is sufficient for this preliminary analysis. We have developed a series of acceptance criteria for whether a particular specimen is likely to yield the correct 14C age. 14C dating of fossil bones not seriously depleted in protein is a straightforward procedure and yields reliable dates.

Two lake and bog sediments have been thoroughly studied using palynological and radiocarbon dating methods. These are the Lembolovskoye Lake section located in the southern part of the Karelian Ithmus and the Mshinskoye bog section located in the southwestern part of the Leningrad province. The data obtained allow us to reconstruct the main features of the vegetation cover evolution, the chronology for the appearance and a real distribution of the main arboreal species from the south of the Leningrad province to the north, and to construct curves of the paleoclimate parameter changes for the area under study. Thirty-six 14C dates were obtained for the Lembolovskoye Lake section (7 m thick). According to those dates, the organic gyttja formation in the lake began 9870 ± 170 BP. Spore-pollen spectra with high percentage of herbs, arborescent, and shrub-birch dated back to the Younger Dryas were found out in clay layers at a depth of 6.5 m. An appearance of spruce and alder pollen is dated at 6860 ± 120 and 7510 ± 150 BP, respectively. The maximal percentage of broad-leaved species falls on the first half of the Atlantic (AT-1). Thirty-two dates were obtained for the Mshinskoye bog section (6 m thick): from 60 : 70 to 9520 ± 170 BP (the last date fixed the beginning of peat formation); 12 palinozones from the Preboreal to the Subatantic were recognized there. The spruce and alder pollen began to appear 7520 ±110 and 7670 ± 130 BP, respectively. The maximal amount of broad-leaved species is observed at 4690 ± 80 BP. The detailed reconstruction of changes in vegetation communities during the Late Glacial and Holocene was correlated with paleoclimatic characteristics, which have been recontructed for the sections under study by using the information from a statistical method of spore-pollen data processing.

Past measurements of the radiocarbon interhemispheric offset have been restricted to relatively young samples because of a lack of older dendrochronologically secure Southern Hemisphere tree-ring chronologies. The Southern Hemisphere calibration data set SHCal04 earlier than AD 950 utilizes a variable interhemispheric offset derived from measured 2nd millennium AD Southern Hemisphere/Northern Hemisphere sample pairs with the assumption of stable Holocene ocean/atmosphere interactions. This study extends the range of measured interhemispheric offset values with 20 decadal New Zealand kauri and Irish oak sample pairs from 3 selected time intervals in the 1st millennium AD and is part of a larger program to obtain high-precision Southern Hemisphere 14C data continuously back to 200 BC. We found an average interhemispheric offset of 35 ± 6 yr, which although consistent with previously published 2nd millennium AD measurements, is lower than the offset of 55–58 yr utilized in SHCal04. We concur with McCormac et al. (2008) that the IntCal04 measurement for AD 775 may indeed be slightly too old but also suggest the McCormac results appear excessively young for the interval AD 755–785. In addition, we raise the issue of laboratory bias and calibration errors, and encourage all laboratories to check their consistency with appropriate calibration curves and invest more effort into improving the accuracy of those curves.

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 of 14C 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.

This list of dates is a continuation of Gakushuin V.Instruments and techniques are essentially the sameas those used for Gakushuin III, IV and V.

The following list comprises a selected number of measurements made up to November 1963. Age calculations are based on a contemporary value equal to 95% of the activity of the NBS oxalic-acid standard, and on a half life for C14 of 5570 ± 30 yr.

Results are expressed in years before 1950 and in the b.c.-a.d. scales. Errors quoted include the standard deviations of the count rates for the unknown sample, the contemporary value, and the background. Calculated errors smaller than 100 yr have been increased by rounding to that figure as a minimum. Sample descriptions have been prepared in collaboration with collectors and submitters.

For several undisturbed sites in Germany, 14C data are reported for soil organic matter (SOM) (4 sites), soil CO2 (10 sites) and dissolved organic carbon (DOC) (1 site). With the assumption of a fast degradable component (lifetime ca. 1 yr) and a slow degradable component (lifetime ca. 100 yr), a range between 0.6 and 1.6 mm yr-1 has been determined for the downward migration rates of soil organic carbon at the sampling sites from the soil 14C data. The soil CO2 measurements show that in deciduous forests the fast degradable component is ca. 60% and the slow degradable component is ca. 40% of the SOM. In coniferous forests this ratio is reversed. The 14C results for DOC could not be explained with the assumption of a first-order decay process. The removal of soil organic carbon by DOC is of minor importance for the estimation of carbon budgets for the investigated site.

During the past three years radiocarbon assay has emerged as a primary tool in the quantitative assignment of sources of urban and rural particulate pollution. Its use in several major field studies has come about because of its excellent (fossil/biogenic) discriminating power, because of advances in 14C measurements of small samples, and because of the increased significance of carbonaceous particles in the atmosphere. The problem is especially important in the cities, where increased concentrations of fine particles lead to pollution episodes characterized by poor visibility and changes in the radiation balance (absorption, scattering), and immediate and possibly long-term health effects. Efforts in source apportionment in such affected areas have been based on emissions inventories, dispersion modeling, and receptor modeling – ie, chemical and physical (and statistical) characterization of particles collected at designated receptor sites. It is in the last category that 14C has become quite effective in helping to resolve particle sources. Results are presented for studies carried out in Los Angeles, Denver, and Houston which incorporated 14C measurements, inorganic and organic chemical characterization, and receptor modeling. The 14C data indicated wide ranging contributions of biogenic and fossil carbon sources – eg, <10% to 60% contemporary (biogenic) in Houston – depending on meteorological, biological, and anthropological activity. The combined (chemical, isotopic, statistical) data point to sources such as vehicles, wood combustion, power plants, and vegetation.