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Applications of Radiocarbon Dating Method


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The main force driving technical development of the radiocarbon dating technique is the wide spectrum of applications that cross interdisciplinary boundaries of Earth and social sciences. This paper provides a very brief overview of some of the many applications of 14C analysis to various studies of human origin and migration, cultures and history, past and present environment, and the human body itself. © 2009 by the Arizona Board of Regents on behalf of the University of Arizona Celebrating 50 Years of Radiocarbon.
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RADIOCARBON, Vol 51, Nr 1, 2009, p 79–90 © 2009 by the Arizona Board of Regents on behalf of the University of Arizona
© 2009 by the Arizona Board of Regents on behalf of the University of Arizona
Celebrating 50 Years of Radiocarbon
RADIOCARBON, Vol 51, Nr 1, 2009, p 79–90 79
Irka Hajdas
Ion Beam Physics, ETH Zurich, Schafmattstr. 20, 8093 Zurich, Switzerland. Email:
ABSTRACT. The main force driving technical development of the radiocarbon dating technique is the wide spectrum of
applications that cross interdisciplinary boundaries of Earth and social sciences. This paper provides a very brief overview of
some of the many applications of 14C analysis to various studies of human origin and migration, cultures and history, past and
present environment, and the human body itself.
From the early days of radiocarbon dating, 2 fields were clearly very interested in this method. Both
archaeology and Earth sciences had their share in the establishment of 14C dating. The first 14C ages
produced on archaeological and geological samples of “known age” illustrated the potential carried
by the new method for these 2 research fields (Arnold and Libby 1949).
Wood samples from the Egyptian tombs of Zoser at Sakkara and Sneferu of Meydum were the very
first archaeological objects 14C dated (Libby et al. 1949) and were used to build the “Curve of
Knowns.” Sixty years ago, 14C dating required several grams of material; therefore, very few pre-
cious objects could have been dated. Nevertheless, the number of dated samples grew rapidly
(Polach 1980). 14C ages revolutionized archaeology by providing a timescale that was independent
of other studies (Libby 1980). At present, archaeology is the main 14C application field, fostering
close collaboration between archaeologists and 14C specialists in various projects.
Quaternary geosciences studies are the second most important application of the 14C dating method,
and have supported the field from the very early days. Soon after publication of the first 14C ages,
new 14C laboratories were established to measure the time observed in deposits studied across the
world. Now, high-quality and high-resolution data are requested from 14C labs. As with archaeology,
Quaternary studies pace the development of the 14C dating method.
The advent of the accelerator mass spectrometry (AMS) technique about 30 yr ago is the best exam-
ple of the interaction between these fields: the technical development pioneered by physicists was
inspired by the need for solutions to problems such as dating of precious objects in archaeology (e.g.
the Shroud of Turin). The ability to count the 14C atoms remaining in the studied object instead of
counting the decay rate revolutionized 14C dating by downscaling the sample size required for age
determination. In effect, new possibilities opened for dating unique objects. In response to this
development, archaeology and Quaternary applications studies expanded, resulting in new problems
to be addressed and solved. Moreover, new applications such as biomedical and environmental stud-
ies joined the spectrum of applications.
From this perspective, the last 60 yr of 14C dating applications appears as a continuous interdiscipli-
nary dialogue supporting the development of the method and expansion of the fields of application.
Each of the applications of 14C dating is characterized by the specific type of samples needed for 14C
dating. Figure 1 shows a breakdown of the most common materials submitted to the AMS 14C lab-
oratory at ETH, Zurich, during the last 15 yr. The most common samples are wood and charcoal,
which are used by archaeology and Quaternary studies. The next group is bones, which are mainly
80 I Hajdas
used in archaeology; however, some bone samples are used for Quaternary or forensic studies. The
next largest group of samples is textiles, followed by foraminifera and mollusk shells, which are typ-
ically used in Quaternary studies. Sometimes mollusk shells are also used in archaeology, being the
byproduct or rubbish/garbage found in remains of prehistoric human settlements. Quaternary stud-
ies and archaeology rely on 14C ages obtained on terrestrial macrofossils, which are short-lived and
free of reservoir age. Dating of the total organic carbon in the bulk sediments is often the only pos-
sible way to obtain the 14C chronology for some lake sediments and decomposed peat. 14C dating of
various fractions of organic carbon in soil is also used to study the turnover time of the soils. Dis-
solved inorganic carbon in groundwater and ocean water is dated for environmental/paleoclimate
studies or oceanography. A small portion of samples includes very specific materials that sometimes
show up in the preparation line. These often address unusual questions that can be answered by 14C
Archaeology: Studies of Human History for the Last 50–60 kyr
The most common samples submitted for 14C dating are bones and charcoal. Less common are tis-
sue and textile samples, hair and leather, which decompose quickly when in unfavorable conditions.
Depending on the location of the archaeological sites, studies have their focus on different periods.
For example, most of the 14C ages obtained during the last 10 yr for 1 archaeological institution in
Switzerland are younger than 4000 BP; however, a small portion (16 samples out of 305) indicates
the presence of sites dating between 5000 and 11,200 BP.
Figure 1 Breakdown of different samples types submitted to the ETH AMS 14C dating laboratory during the last 15 yr
'( 
Applications of 14C Dating Method 81
Our example from Switzerland reflects the tendency in Europe, where most archaeological finds are
younger than 10 kyr BP. Nevertheless, 14C ages are also obtained for the early Neolithic and
Mesolithic. Nearly 800 charcoal samples recovered during extensive archaeological excavations
accompanying the highway construction around Lake Neuchâtel, Switzerland, documented the
whole spectrum of human occupational activities between 14,000 cal BP and the present (unpub-
lished data, Archaeological Survey of Neuchâtel, Switzerland).
World archaeology might have different age distribution, and local patterns influence the distribu-
tion of 14C ages of individual laboratories dependent on the projects. One international project in
which ETH laboratory was involved was the construction of the chronology of Scythian burials at
Pazyryk and Ulandryk in the Altai Mountains. The Scythian kurgans (tombs) found in the steppes
of Eurasia reveal remains of the fascinating world left behind by nomadic people who were known
for their love of horses and gold (Bachrach 1971). Despite the fact that organic matter was well pre-
served in the permafrost environment, precise dating of the kurgans posed a challenge. Due to the
14C age plateau at 2500 BP, calibrated ages for most of the 14C ages fall into the period between 700
and 300 BC. However, the trunks of larch used for building the tombs were perfectly preserved,
which allowed dendrochronology to be applied. The combination of 14C dating and the tree-ring
chronology enables overcoming problems caused by the tentative tree-ring master curve of this
region. A sequence of ages obtained for a tree was placed on the calibration curve, which set the cal-
endar age of the last ring in the range between 296 and 330 BC (Figure 2) (Hajdas et al. 2004).
Figure 2 14C dating of a larch log from the Ulandryk kurgan. The closed circles are 14C ages obtained by Hajdas et al.
(2004); the open circles are data from Slusarenko et al. (2002). Modified from Hajdas et al. (2004).
C age BP
cal BC
296 to 330 BC
82 I Hajdas
Late Paleolithic sites across Europe and Eurasia contain mostly charcoal or bones, which are suit-
able for dating. The limit of the 14C dating method at around 50 kyr still allows for 14C dating of the
Middle to Upper Paleolithic transition and the first appearance of anatomically modern humans in
Europe as well as remains of the last Neanderthals (Conard and Bolus 2003; Conard 2006). Answer-
ing the questions of coexistence of these 2 species relies on accurate chronologies of this time inter-
val. Some of the 14C ages reported thus far suggest that Neanderthals survived into to the period 30–
40 kyr BP, thus documenting the presence of anatomically modern humans (for discussion, see
Klein 2003). At present, this is one of the challenges faced by 14C dating, because in this time win-
dow calibration problems add to the problem of 14C dating at the limit of the method.
Quaternary Studies and Climate Change
The last 50 kyr in Earth history includes the last glacial cycle and 11,000 yr of Holocene warm cli-
mate. The changes of climate experienced by the Earth left clear imprints on the landscape. 14C dat-
ing of these natural archives provides the time frame for climatic fluctuations. Lake sediments are
usually dated using terrestrial macrofossils, which are free of the “hard water” effect, i.e. old carbon
present in lake water. Total organic carbon is used when the lake is considered to be free of dissolved
old carbonates washed in from the catchment area.
Deep-sea cores are dated using 14C ages of foraminifera shells. This application only became possi-
ble with the advent of the AMS measurement technique, which replaced dating of bulk carbonate by
decay counting. The periods of interest within the limit of the 14C dating method include oxygen iso-
tope stage 3, last glacial maximum (LGM), last deglaciation, and the Holocene. From its early days,
14C dating provided the first numerical ages for the boundaries of these periods. Detection of mil-
lennial timescale fluctuations, the so-called Daansgaard-Oeschger (DO) events, in Greenland ice
cores (Dansgaard et al. 1993) prompted more detailed investigations of continental and marine
records. Moreover, higher resolution is required for observation and correlation of abrupt climatic
events. Leads and lags between changes observed at different sites could only be resolved with good
chronological time frames. These are essential for understanding the mechanisms that caused the
particular events. For example, the timing for the beginning of the Younger Dryas, i.e. the last cold
spell of the Late Glacial observed around 11 and 10 kyr BP in European lakes and peat bogs, was
established using 14C dating (Mangerud et al. 1974). Many sites around the world have shown
Younger Dryas-type cooling at the end of the Late Glacial with 14C ages close to 11 kyr BP (for a
review, see Peteet 1995). However, it has also been shown with the help of 14C dating that the timing
of the Younger Dryas as observed in terrestrial and marine records of the North Atlantic region is
different from the cold reversals at some locations from the Southern Hemisphere (Patagonia and
New Zealand; Hajdas et al. 2003, 2006).
The early 1990s brought attention to another type of climatic event that was first observed in marine
cores recovered from the North Atlantic. Layers of ice-rafted debris (IRD) are found in sediment
cores of the North Atlantic, documenting paths of the iceberg fleets floating southwards (Heinrich
1988; Bond et al. 1992). Chronologies of these cold Heinrich events (HE) are based on 14C dating
of foraminifera shells found in those layers or in sediments bracketing them. Four of the HE
occurred during the last 45 kyr and can be 14C dated. Correlation of globally distributed sites that
record the impact of HEs is quite often based on 14C chronologies (Broecker and Hemming 2001;
Hemming 2004).
Reliable 14C ages are essential for the approaches listed above, especially when the ages are close to
the limit of the method. Removal of contamination is one of the problems addressed by 14C labora-
tories. For example, 14C dating of a mammoth find from Niederweningen was performed on mam-
Applications of 14C Dating Method 83
moth tusk and bones as well as on peat and wood from the section in which the mammoth was found
(Figure 3). The precleaned gelatin fraction, which was treated with base (Arslanov and Svezhentsev
1993) and/or ultrafiltration (Brown et al. 1988), yielded a consistent 14C age of 45,720 ± 710 BP
(Hajdas et al. 2007, 2009). The same age was obtained on a sample taken from the top of the mam-
moth peat layer (Figure 3). The coherent 14C ages suggest the effectiveness of the applied treat-
Another archive of past climate changes is groundwater. Stable isotopes (δD, δ13C, δ18O) and noble
gases (Ar, Kr, Ne, Xe) in groundwater record the temperature of the air at the time of recharge. This
last encounter and exchange of gases with the atmosphere can be traced back by 14C dating of dis-
solved inorganic carbon, DIC (i.e. CO2, HCO3–, CO3–). Studies of the paleo-aquifer around the
world show that during the LGM temperatures were lower by 3–5 °C even at low latitudes (Stute et
al. 1995a,b). Figure 4 shows the noble gas temperature reconstructions in the Sahel region (Beyerle
et al. 2003). The gap in the record observed between 23 and 15 kyr BP indicates reduced groundwa-
ter recharge during the arid LGM.
The Oceans—Present and Past
Most of the 14C produced in the atmosphere ends up entering the ocean, which is the largest carbon
reservoir. CO2 exchange rates are based on tracking the dissolved CO2 that reflect “bomb peak” 14C,
i.e. the excess of 14C produced artificially during the 1950s/60s nuclear tests. Mapping the distribu-
tion of natural 14C and bomb 14C allows reconstruction of the ocean circulation. In the GEOSECS
project (1972–78), samples of water were collected from ships crossing the oceans and analyzed for
14C content. In the early days, when the conventional technique required grams of carbon, 200-L
water samples had been collected. These numerous measurements allowed reconstruction of the
regions with sinking water masses (deep-water produced) and the upwelling regions where “old”
waters come to the surface (Broecker et al. 1978, 1985).
Figure 3 14C chronology of a mammoth find in Niederweningen, Switzerland (Hajdas et al. 2007, 2009)
Top of peat layer:
45,430±1020 BP
Mammoth bone:
45,720±710 BP
84 I Hajdas
The pathways of water masses can be traced by 14C dating of fossils in the deep-sea sediments.
Shells of plankton foraminifera register the 14C signature of the mixed-layer waters, whereas calcite
of the benthic zooplankton reflects the 14C content of the bottom water (i.e. its 14C age). Paleoreser-
voir ages are only partially known at present. However, even this limited picture suggests significant
fluctuations occurred in the past (Bondevik et al. 2006).
14C Dating and Environmental Studies
Anthropogenic changes in the atmospheric 14C content caused by fossil fuel combustion and the
addition of “14C-free” carbon (Suess effect), as well as the nuclear tests (14C bomb peak), greatly
affected the 14C dating of the last 150 yr. Measurements of the atmospheric 14C content have been
performed during the last 50 yr (Hua and Barbetti 2004; Levin and Kromer 2004). Stations located
around the world collect air samples from pristine and urban areas. While the bomb 14C, which is a
very useful tracer for environmental studies (Levin and Hesshaimer 2000), is leveling off mainly
due to the ocean uptake, the fossil fuel impact is observed especially in the urban regions (Levin et
al. 2008). One of the recent applications of 14C analysis is monitoring biogenic fuel for clandestine
additions of fossil fuel.
Studies of sources of carbonaceous particles (aerosols) in the atmosphere use 14C analysis to deter-
mine portions of the OC (organic carbon, modern) and EC (elemental carbon, fossil fuels) (Currie
et al. 1997). Other environmental studies make use of bomb 14C. For example, estimation of the
turnover time of soils is possible with the help of 14C measurements made on various fractions
Figure 4 Calibrated 14C ages of groundwater provide a timescale for temperature changes (nobel gas temperature
[NGT]) in the Sahel region (Figure 2 from Beyerle et al. 2003). Reprinted with permission.
0 5 10 15 20 25 30 35 40 45
NGT (°C)
Groundwater age (kyr BP)
Younger Dryas
Major dry periods
Applications of 14C Dating Method 85
(pools) of soil organic matter SOM. In a study of Sierra Nevada soils, Trumbore et al. (1996) mea-
sured 14C content of transects of pre- and post-1963 soils. The results showed that fractions with dif-
ferent density have different turnover time. The low-density fraction (<2 g/cm3) is the fastest of the
SOM, showing a quick response to the bomb 14C signal and high 14C content for pre-bomb soils.
The hydrolyzable high-density fraction (>2.0 g/cm3) is the intermediate portion reacting slower than
the low-density fraction. The slowest pool is made up of high-density nonhydrolyzable (>2.0 g/cm3)
portions of SOM, which showed the lowest pre-bomb 14C concentrations and lowest impact of
bomb 14C (Figure 5).
Figure 5 Changes in 14C content of different fractions of
soils collected between 1959 and 1992 on Sierra Nevada
slopes (Figure 3 from Trumbore 1997). Reprinted with
86 I Hajdas
Compound-Specific Radiocarbon Analysis (CSRA)
Thanks to a technical development allowing 14C analysis of samples containing micrograms of car-
bon, 14C analysis at the molecular level became possible (Currie et al. 1985). Ingalls and Pearson
(2005) gave an overview of the applications developed in the first decade of CSRA. Chromato-
graphic separation and 14C dating of individual biomarkers from deep-sea sediments provide infor-
mation about sources of various components as well as the processes of organic carbon transport,
degradation, and burial. A similar approach can be applied to the determination of various compo-
nents of soils (Rethemeyer et al. 2004). Moreover, attempts are being made to use CSRA to date
paleoproxy records. One of the great dreams of researchers working with sediment cores from the
Southern Ocean, where hardly any foraminifera can be found, is obtaining 14C chronologies of their
records (Zheng et al. 2002). Ingalls et al. (2004) proposed CSRA of diatom frustules, which could
help to bypass the lack of foraminifera. Another application of CSRA, tested more than a decade ago
but not fully exploited yet, is dating bone specific amino acids to avoid intrusive carbon that might
alter the 14C age of the bone (Van Klinken et al. 1994).
The subject of 14C in the human body has been studied already in the early years of 14C dating. The
sudden appearance of the bomb peak provided an excellent tracer, which allowed estimation of the
turnover time of carbon in the human body (Broecker et al. 1959; Libby et al. 1964; Nydal et al.
1971). Except for bone collagen, most body organs have a short turnover time and are close to the
contemporary levels of atmospheric 14C. Moreover, the dietary effect (such as the impact of seafood
on 14C content) has been established, which is of great use for 14C dating in archaeological studies
(Harkness and Walton 1972).
Because of the small amount of carbon required (down to 2.5 μg; Ruff et al. 2007), dating of specific
cell types and molecules is now possible. A clinical study by Robertson et al. (2001) determined the
formation of senile plaques (SP) and neurofibrillary tangles (NFT). Two characteristic features are
observed in the human brain affected by Alzheimer’s disease. The study aimed to establish the chro-
nological relation between the formation of NFT and SP and the onset of Alzheimer’s symptoms.
Results suggested that in most cases NFT and SP started to accumulate after the first symptoms were
The existence of the bomb 14C spike provides a marker for the generation born in the late 1950s and
later. As the bomb peak is leveling off, such studies might become less applicable to later genera-
tions. Spalding et al. (2005a) applied AMS 14C dating of genomic DNA, which retains its original
carbon without exchange. Dating of the formation time of the cells in the various regions of the
human brain can help answer questions of possible neurogenesis. The 14C concentration in genomic
DNA of the cortex neurons indicated its formation at birth with little indication of later formation of
the neurons (Spalding et al. 2005a).
Determination of the time of death of an organism is the direct information of 14C dating and is
applied in forensic investigations. 14C dating of a glacier mummy found in the Alps in 1991 is a pop-
ular example of dating discovered human remains. The archaeological context found with Ötzi
(named after the Ötztal Alps where it was found) indicated that the body was not from the last
decades; instead, it was dated to 4546 ± 17 BP, i.e. 3350–3110 BC (Bonani et al. 1994). However,
in some cases such a context is missing or the time window must be estimated more precisely. Bomb
14C dating is a useful tool for the last 60 yr for it allows pinpointing the time of death (Wild et al.
Applications of 14C Dating Method 87
2000; Tuniz et al. 2004). It has also been proposed to use 14C dating of tooth enamel to help estimate
the time when the tooth was formed, and therefore the year of the birth (Spalding et al. 2005b).
Art History, Textiles, and Fraud Detection
Art objects have been found in Middle Paleolithic layers, mostly made of bone, antler, or ivory,
which are robust material and can be 14C dated. Typically, however, the pieces are so precious that
their dating is performed on associated material, i.e. bone or charcoal found in the same layer. In
some cases, the AMS technique allowed direct dating of unique objects such as the prehistoric paint-
ings from Chauvet Cave (France), which were created between 29,700 and 32,900 BP (Clottes et al.
An overview of the history of textiles is given by Barber (1992). The first indication of weaving was
found for the early Neolithic. Impressions of textiles discovered in Jarmo, Iraq, might be as old as
7000 BC, and a linen cloth created around 6500 BC was found in a dry cave in Nahal Hemal, Israel.
In the 1960s, fragments of textiles were recovered from the Anatolian prehistoric town of Çatal
Höyük that dated back to 6000 BC. The first woven textiles in Egypt appeared around 5000 BC.
Linen textiles from Swiss Neolithic sites date to around 3000 BC. However, most of these objects
are not directly 14C dated because their discoveries were made before or in the early days of the 14C
dating method.
Following the dating of the Shroud of Turin (Damon et al. 1989), 14C dating of unique textiles
became reality. Van Strydonck et al. (2004) compared 14C ages of Roman and Coptic textiles with
their art historical dating, showing that the methods provide similar precision. Often discussed are
the “frustrations” caused by the existence of wiggles in the final 400 yr of the calibration curve.
Many art objects and textiles date to this time period; consequently, their calibrated ages represent
wide ranges of calendar ages, but additional information (historic notes, ownership record, style,
pigment) can help to narrow the range. For example, the 14C age of the oldest knotted pile rug found
in Kurgan V of Pazyryk is 2245 ± 35 BP (Rageth 1999) and falls in the region of the age plateau at
2200 BP. However, with the help of chronologies built for Kurgan II and other kurgans of the
Pazyryk culture, as described above, the calendar age of this textile can be placed between 383 and
238 BC (Hajdas et al. 2004).
Art forgery creates and/or sells works that imitate original pieces of art. There are objects that are
attributed to famous artists but also antique objects that are highly prized because of their age. In
some cases, 14C dating is able to detect false material by measurement of the 14C content of the
material used. Most cases are straightforward and forgery is detected as post-AD 1950 products. But
some pieces are created on old materials in order to bypass the bomb peak signature. Such attempts
indicate that there is a common awareness of the potentials that 14C dating has for the detection of
forgery. However, the ability to acquire material of the desired age in order to produce sophisticated
forgery is rather limited.
Recent (post-AD 1950) attempts to imitate ancient textiles can also be detected. Nearly 1% of all the
textiles dated at the ETH laboratory appear to be post-AD 1950 or modern, i.e. containing bomb 14C.
The forgeries that predate the bomb peak are less obvious and their detection requires expertise in
other parameters such as pigments, styles, etc. Moreover, a possibility of mixing or fabricating
material to obtain the desired 14C age cannot be excluded, as reported by Nadeau et al. (2008).
88 I Hajdas
As foreseen in the early days of the method, 14C dating can be used in a wide spectrum of applica-
tions in various fields. The methodological and measurement developments that happened during
the last 6 decades were only possible because of interdisciplinary collaboration. Also, the future of
14C applications relies on communication between laboratories and the users. The growing number
of laboratories allows much shorter turnaround time for 14C ages and much higher throughput. Thus,
high-resolution chronologies are becoming a common practice. Environmental and biomedical
studies are increasing the sample load, and the dynamic field of CSRA is adding new applications
and giving new opportunities of tracking contamination in samples.
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... 14 C dating method limits measurement to Middle and Upper Paleolithic eras and the first appearance of modern humans and remains of the last Neanderthals. (Hajdas, 2009) Climate Change and Environmental Studies 14 C dating provides the time scale for climatic variations like the last glacial cycle and Holocene warm climates. Air samples from natural and urban areas are collected via various stations located around the globe. ...
... The fossil fuel impact and other environmental impacts can be studies using 14 C. Monitoring biogenic fuel for illegal additions of fossil fuel is one of the most contemporary applications of 14 C analysis. (Hajdas, 2009) The Oceans-Present and Past ...
... Mixedlayer water 14 C signature is imprinted on shells of plankton whereas 14 C content of the bottom water is imprinted in the calcite of the benthic zooplankton. (Hajdas, 2009) ...
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This is a review paper on Carbon Dating
... Radiocarbon ( 14 C) dating in this period, however, is a well-known challenge due to a plateau feature characterizing the calibration curve resulting almost constant 14 C ages between ∼800 to ∼400 BC (Friedrich and Hennig 1996;Pichler et al. 2011;Jacobson et al. 2018). 14 C dating of a single sample from a period of time that coincides with a plateau may lead to similar 14 C ages applying to a wide range of calendar dates sometimes greater than a couple of centuries, creating imprecision, ambiguity for archaeological dating (Hajdas 2009;Manning et al. 2020). Development of yearly-resolved 14 C datasets for certain parts of this challenging period in order to improve the calibration accuracy is an on-going effort (Jacobson et al. 2018;Jull et al. 2018;Fahrni et al. 2020). ...
Archaeological excavations unearthed three burial mounds between 1983 and 1986 at Fehérvárcsurgó (Hungary). Based on the archaeological determination the site was dated to the Early Iron Age. A complex wooden architecture was observed in the largest tumulus containing inner and outer beam constructions separated by stone blocks. Dendrochronological and radiocarbon ( ¹⁴ C) analyses were performed on conserved logs (n=5) to constrain the felling date of the timber, identified as oak, and the construction period of the tumuli. The four longest ringwidth series were synchronized providing a 153-yr-long floating chronology. Five blocks were removed from the cross sections and accelerator mass spectrometry (AMS) ¹⁴ C analysis was performed on the separated α-cellulose. A wiggle-matching procedure was employed as the ¹⁴ C ages were in agreement with their relative position in the tree-ring sequence and concurred with the expected archaeological period. The calibrated age range of the last extant ring is 747–707 cal BC (95.4%). The earliest possible felling date of the trees used in the construction was between 735 and 695 BC considering the missing sapwood. This is the first ¹⁴ C dated tree-ring width chronology from the Early Iron Age in Hungary providing a valuable reference for dendroarchaeological studies along the eastern border of the Hallstatt Culture.
... The scope of this paper is to present and discuss a series of events that took place in a unique region of central Valcamonica during the Middle Ages, and to define their reliability with the help of archaeological and scientific analyses (see Miramont et al. 1999;Hajdas 2009;Nussbaumer et al. 2011). The article is focused on the legend of St. Glisente, formerly a knight of Charlemagne (Zallot 2012, p. 217), who, according to the legend (Cominelli 2012, p. 155), lived in hermitage in these mountains during a period whose chronology is still debated. ...
This paper discusses the legend of St. Glisente that is still very popular in some villages of Valcamonica (Central Alps of Lombardy, northern Italy). According to one of the narratives the saint, formerly a knight of Charlemagne, after serving the king for many years during his wars for the Christianization of the Lombard tribes, decided to retire in the high mountains of central Valcamonica. Here he lived as a hermit in a small rock-shelter that opens at 2000 m of altitude at present locally called “niche of St. Glisente”. The archaeological surveys carried out along the watershed that separates Valcamonica from Valtrompia led to the discovery of many archaeological sites. They show that these mountains were settled since the beginning of the Holocene and also during the Middle Ages. The radiocarbon dates obtained from a few fireplaces show that some kind of human activity took place mainly at the turn of the 1st millennium AD in the saddle where St. Glisente rock-shelter opens at 2000 m of altitude.
... Radiocarbon dating has transformed our capacity to develop climatic, environmental, and human histories (e.g. Bayliss, 2009;Hajdas, 2009;Wood, 2015). Indeed, charcoal, also known as pyrogenic carbon, char and black carbon (Meredith et al., 2012), has become one of the most commonly used materials for the generation of radiocarbon chronologies (e.g. ...
Pyrogenic carbon (charcoal, black carbon, elemental carbon) is one of the most common materials used for radiocarbon dating of terrestrial samples. However, exogenous carbon contamination can compromise the accuracy of radiocarbon ages. This study presents the results of two chemical pretreatments prior to hydrogen pyrolysis (hypy) as improved protocols for the isolation and decontamination of pyrogenic carbon, i) a simple acid-oxidation step (A-Ox/hypy) and ii) acid-base-acid (ABA/hypy). The A-Ox/hypy protocol uses HNO3 and H2O2, while ABA/hypy uses HCl and NaOH. Both pretreatments remove labile and inorganic carbon before hypy, decreasing the potential for in situ production of pyrogenic carbon during the hypy reaction. The effectiveness of each protocol was directly measured on charcoal artificially produced at 350 °C, 450 °C and 550 °C from radiocarbon-free wood, and exposed to environmental contamination for 1–3 yrs. The results show a >94% reduction in carbon contamination for the 450 °C and 550 °C charcoal samples occurred using A-Ox/hypy, but this treatment was less effective for the 350 °C charcoal. A >99% reduction in carbon contamination in all charcoal samples examined occurred using ABA/hypy. The A-Ox/hypy protocol was further tested on cave guano sediments, which had previously reported erroneous dates following simple organic solvent extraction followed by ABA pretreatment. Effective decontamination was achieved using A-Ox/hypy on the guano, which corrected a radiocarbon age reversal. Overall, ABA/hypy effectively decontaminated the charcoals and was a more efficient pretreatment for charcoal than A-Ox/hypy, however resulting in larger sample mass loss. Therefore, ABA/hypy is the recommended protocol for older (>30,000 14C yr BP) charcoal or sediment samples, or where date accuracy is imperative, while A-Ox/hypy represents an improved protocol for the quick and cost-effective measurement of younger samples (<30,000 14C yr BP) when sample size is of concern
... 1977 など) 。 今日では 14 C 年代の信頼性は多くの研究者によ り高く評価され,地形学や第四紀学など自然地理 学に関連する多岐の研究分野においても 14 C 年代 やその較正年代が使用されている (Fairbridge, 1961 ;中田ほか,1978 ;小元,1991, 1998Hajdas, 2009 ...
... Since the atmospherically sourced DIC pool is the primary carbon source for photosynthesis by aquatic autotrophic organisms such as phytoplankton (Ingalls and Pearson 2005; McNichol and Aluwihare 2007), this result suggests the preferential consumption of recently photosynthesized material by mesozooplankton, rather than indiscriminant feeding on POM of varied age signatures. Few studies have attempted to trace the flow of organic matter through trophic levels utilizing radiocarbon signatures in conjunction with traditional bulk stable isotope analysis (Hajdas 2009), and furthermore, never has the CSIA food web structure method developed by Chikaraishi et al. (2009) been combined with extensive radiocarbon analysis of the species under investigation. This CSIA based food web structure is developed by assigning each sampled species a quantified trophic position value, based on the ratio of stable nitrogen isotopes in the amino acids phenylalanine and glutamine (Chikaraishi et al. 2009). ...
A suite of isotopic methods were combined to provide a comprehensive investigation of organic matter transfer and consumer-resource links in a large lake food web. We applied compound specific isotope analysis (CSIA) of nitrogen within amino acids of organisms, a relatively new method and one not yet widely applied to large lake systems, to determine the trophic positions of several dominant species. Comparison of this CSIA trophic designation to those calculated by traditional bulk stable carbon and nitrogen isotope ratios, as well as gut content analyses, revealed this CSIA method to be the most representative of known trophic links in Lake Superior. Limnocalanus macrurus, an omnivorous copepod, was found to occupy a trophic position higher than would have been predicted based on gut analyses, and one full trophic position above primary consumer Daphnia. Radiocarbon analysis of bulk zooplankton and fish tissue was employed as a modern carbon tracer to elucidate the relative ages of carbon incorporated into, and propagated through, the food web. Comparison of animal tissue, non-living carbon pools (DOC, DIC), and POC radiocarbon content indicate the food web is supported predominately by newly synthesized autochthonous material. The uniquely depleted radiocarbon signature of the benthic amphipod Diporeia, attributed to consumption of aged sedimentary or allochthonous material, was not reflected in its known predators, indicating little overall incorporation of that aged carbon source into the pelagic food web. This multi-method isotopic investigation extends our understanding of food web structure and organic matter flow in this large lake.
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With the conclusion of the Last Glacial Maximum (LGM), about 20 000 years ago, ended the most recent long-lasting cold phase in Earth history. This last glacial advance left a strong observable imprint on the landscape, such as moraines, trimlines and other glacial geomorphic features. These features reflect the extent of former glaciers and ice caps, which in turn provides information on past temperature and precipitation conditions. Here we present an inverse approach to reconstruct the equilibrium line altitudes ( E ) from observed ice extents. The ice-flow model is developed solving the mass conservation equation using the shallow ice approximation and implemented using Graphical Processing Units (GPUs). We present the theoretical basis of the inversion method, which relies on a Tikhonov regularization, and demonstrate its ability to constrain spatial variations in mass balance with idealized and real glaciers.
This paper describes the systematics of the main dating systems for geological and environmental processes during the late-Quaternary (
Terrestrial cosmogenic nuclides (TCN) have widely been used as proxies in determining denudation rates in catchments. Most studies were limited to samples from modern active streams, thus little is known about the magnitude and causes of TCN variability on millennial time scales. In this work we present a 6 kyrs long, high resolution record of 10Be concentrations (n = 18), which were measured in sediment cores from an alluvial fan delta at the outlet of the Fedoz Valley in the Swiss Alps. This record is paired with a three-year time series (n = 4) of 10Be measured in sediment from the active stream currently feeding this fan delta. The temporal trend in the 10Be concentrations after correction for postdepositional production of 10Be was found to be overall constant and in good agreement with the modern river 10Be concentration. The calculated mean catchment-wide denudation rate amounts to 0.73 ± 0.18 mm/yr. This fairly constant level of 10Be concentrations can be caused by a constant denudation rate over time within the catchment or alternatively by a buffered signal. In this contribution we suggest that the large alluvial floodplain in the Fedoz Valley may act as an efficient buffer on Holocene time scales in which sediments with different 10Be signatures are mixed. Therefore, presumable variations in the 10Be signals derived from changes in denudation under a fluctuating Holocene climate are only poorly transferred to the catchment outlet and not recorded in the 10Be record. However, despite the absence of high frequency signals, we propose that the buffered and averaged 10Be signal could be meaningfully and faithfully interpreted in terms of long-term catchment-averaged denudation rate. Our study suggests that alluvial buffers play an important role in regulating the 10Be signal exported by some alpine settings that needs to be taken into account and further investigated. This article is protected by copyright. All rights reserved.
Radiocarbon dating is an important tool for the determination of the age of many samples and covers the time period of approximately the last 50,000 years. We can use radiocarbon dating to estimate the age of a wide variety of carbon-containing materials. Both organic or inorganic materials at the Earth's surface and in the oceans form in equilibrium with atmospheric carbon-14. This makes it an important tool for the understanding of processes during the time-scale of modern humans, from the last glacial-interglacial transition, to recent archaeological studies of art works. We present an overview of the technique, its advantages, assumptions and limitations. We also emphasize dating interesting objects. Radiocarbon has been applied to dating many historical artifacts and archaeological applications. Some specific examples including dating of famous artifacts of artistic, religious and scientific interest are discussed.
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We explored the reliability of radiocarbon ages obtained on organic carbon phases in opal-rich Southern Ocean sediments. Paired biogenic carbonate and total organic carbon (TOC) 14C analyses for three Southern Ocean cores showed that the TOC ages were systematically younger than the carbonate ages. Carbonate ages were consistent with oxygen isotopic and bio-stratigraphy, indicating error in TOC ages that could be explained by 5-24% of modern carbon contamination of TOC samples. Two possible sources of contamination are: 1) adsorption of atmospheric CO 2 or volatile organic compounds to reactive opal surface sites, and 2) fixation of atmospheric CO 2 by chemosynthetic bacteria during core storage. In an effort to reduce the modern carbon contamination, diatoms were separated from sediments, purified, and pre-oxidized by concentrated nitric and perchloric acids to permit dating of opal-intrinsic organic carbon (∼0.1-0.3% by weight). 14C ages of chemically pre-oxidized opal showed a significant amount of modern carbon contamination, from 11 to 32%, indicating adsorption from the atmosphere of modern carbon onto opal surfaces that were previously cleaned by acid oxidation. Several experiments designed to eliminate the modern C contamination were attempted, but so far we have not been able to obtain a radiocarbon age on 14C-dead Southern Ocean opal-rich sediments, either bulk TOC or purified diatom opal samples, as old as our procedural blank.
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14C ages of samples from the Otztal Ice Man, found on the Hauslabjoch in the Tyrolean Alps in September 1991, were determined using accelerator mass spectormetry (AMS). Uncalibrated 14C ages of 4555±34 BP, 4560±65 BP and 4535±60 BP were measured on tissue (mean of four samples), bone and grass, respectively, from the Ice Man. The mean of all our measurements is 4550±27 BP. -Authors
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 CO 2 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 CO 2 into the Cs sputter ion source and ensures stable measuring conditions. The system is based on a syringe in which CO 2 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 14 C/ 12 C could be repeated within statistical errors to better than 1.0% and the 13 C/ 12 C ratios to better than 0.2%. The blank was <1 pMC.
A comprehensive tropospheric 14 CO 2 data set of quasi-continuous observations covering the time span from 1959 to 2003 is presented. Samples were collected at 3 European mountain sites at height levels of 1205 m (Schauinsland), 1800 m (Vermunt), and 3450 m asl (Jungfraujoch), and analyzed in the Heidelberg Radiocarbon Laboratory. The data set from Jungfraujoch (1986–2003) is considered to represent the free tropospheric background level at mid-latitudes of the Northern Hemisphere, as it compares well with recent (yet unpublished) measurements made at the marine baseline station Mace Head (west coast of Ireland). The Vermunt and Schauinsland records are significantly influenced by regional European fossil fuel CO 2 emissions. The respective Δ 14 CO 2 depletions, on an annual mean basis, are, however, only 5 less than at Jungfraujoch. Vermunt and Schauinsland both represent the mean continental European troposphere.
A bibliography of the radiocarbon dating literature for the years 1948-68, which is in the process of compilation, is examined and a format is proposed. A survey of literature growth has also been undertaken. This enables projections of the numbers of publications referring to radiocarbon dating to be made. The estimated number of publications for the year 1978 is compared to literature retrieval obtained by interrogating eight relevant computer data bases. It is concluded that computer information retrieval is not satisfactory. Bibliographic control of radiocarbon dating literature would be best achieved by a bibliography dedicated to the subject and updated at regular intervals.
A comprehensive tropospheric (CO2)-C-14 data set of quasi-continuous observations covering the time span from 1959 to 2003 is presented. Samples were collected at 3 European mountain sites at height levels of 1205 m (Schauinsiand), 1800 m (Vermunt), and 3450 m. as] (Jungfraujoch), and analyzed in the Heidelberg Radiocarbon Laboratory. The data set from Jungfraujoch (1986-2003) is considered to represent the free tropospheric background level at mid-latitudes of the Northern Hemisphere, as it compares well with recent (yet unpublished) measurements made at the marine baseline station Mace Head (west coast of Ireland). The Vermunt and Schauinsland records are significantly influenced by regional European fossil fuel CO2 emissions. The respective Delta(CO2)-C-14 depletions, on an annual mean basis, are, however, only 5 parts per thousand less than at Jungfraujoch. Vermunt and Schauinsland both represent the mean continental European troposphere.
A representative selection of Roman and Coptic textiles is used to compare the radiocarbon dating results with the chronology proposed by art historians. In some cases, the comparison was made on individual objects, but in other cases, groups of stylistically and/or technologically related textiles were compared. In the case of the latter, the interquartile range was calculated. The results of this comparison show that some individual samples and groups are dated older than expected, while for another group the opposite is the case. One group was matching well with the presumed period as a whole, but not on the basis of the individual pieces. The analyses showed the necessity of 14C dating to obtain a more accurate dating of Coptic textiles.
The Chauvet Cave is original from several points of view. The animals most often painted or engraved in it are scarce in cave art. The techniques used by the artists were superbly mastered. They made use of perspective and stump drawing, they scraped the walls or the outlines of some animals to enhance their drawings. Radiocarbon datings are coherent and set some of those paintings around 31 000 BP. -from English summary