Continental margins play a fundamental role in the carbon cycle as primary oceanic locations of organic (OC) burial. However, gaps remain our understanding factors controlling distribution and preservation matter (OM) these heterogeneous dynamic systems. In particular, impact hydrodynamic processes on age, abundance, stable isotopic composition sedimentary OC is poorly constrained. Here, we characterize present bulk grain-size sediment fractions from seven continental margin settings. Our...

Abstract Age estimates from bomb 14 C dating conflict with a well-recognized age reading protocol (grinding, polishing and staining in the sagittal plane) for otoliths of European eel ( Anguilla anguilla ). Proper alignment calculated hatch years measurements taken earliest otolith growth—among smallest extractions to date successful analysis due advent gas-AMS—was not achieved using an accepted method. The realignment values tropical reference chronology, which is most applicable Sargasso...

We examine instrumental and methodological capabilities for microscale (10–50 μg of C) radiocarbon analysis individual compounds in the context paleoclimate paleoceanography applications, which relatively high-precision measurements are required. An extensive suite data 14C-free modern reference materials processed using different methods acquired an elemental-analyzer–accelerator-mass-spectrometry (EA-AMS) setup at ETH Zurich was compiled to assess reproducibility specific isolation...

Significance Can radiocarbon ( 14 C) dating uncover modern forgeries? Radiocarbon has the potential to answer question of when an artwork was created, by providing a time frame material used. In this study we show that with two microsamples (<500 μg), from both canvas and paint layer itself, forgery could be identified. The is consistent purported attribution 19th century; however, C age gained on contradicts as it offers clear evidence for post-1950 creation. Thus additional reveals...

Although regulatory guidances require human metabolism information of drug candidates early in the development process, mass balance study (or hADME study), is performed relatively late. studies typically involve administration a 14C-radiolabelled where biological samples are measured by conventional scintillation counting analysis. Another approach therapeutic doses containing 14C-microtracer followed accelerator spectrometry (AMS) analysis, enabling completion much earlier. Consequently,...

A new instrumental setup, combining laser ablation (LA) with accelerator mass spectrometry (AMS), has been investigated for the online radiocarbon ((14)C) analysis of carbonate records. Samples were placed in an in-house designed LA-cell, and CO2 gas was produced by using a 193 nm ArF excimer laser. The (14)C/(12)C abundance ratio then analyzed ion source AMS. This configuration allows flexible time-resolved acquisition (14)C profiles contrast to conventional measurements, where only bulk...

Context The potential lifespan of alligator gar (Atractosteus spatula) is currently unknown. A previous study applied bomb radiocarbon (14C) dating to establish ages >60 years, but maximum age was limited by the rise bomb-produced 14C in 1950s. Aims An exceptionally large specimen (2.6 m, 148 kg) captured Mississippi and otolith growth zones revealed an estimate 95 years. This provided opportunity apply new technology validate gar. Methods Developments accelerator mass spectrometry (AMS)...

Abstract. Leaf wax n-alkanes are increasingly used for quantitative paleoenvironmental reconstructions. However, this is complicated in sediment archives with associated hydrological catchments since the stored can have different ages and origins. 14C dating of yields independent age information these proxies, allowing their correct interpretation. This also holds true fluvial sediment–paleosol sequences (FSPSs) that integrate two n-alkane signals: (i) a catchment signal sediments (ii) an...

Bomb-produced 14C has been used to make valid estimates of age for various marine organisms 25 years, but fish ages that lead birth years earlier than the period increase in lose their time specificity. As a result, bomb dating is limited minimum from last year prebomb levels because temporal variation surface layer negligible decades before c. 1958. The longevity red snapper (Lutjanus campechanus) Gulf Mexico remains unresolved despite forms support near 50–60 years. Although and growth...

Abstract Conventional radiocarbon analysis of carbonate records with accelerator mass spectrometry (AMS) is time consuming and the achievable spatial resolution limited, because individual samples have to be taken need converted graphite for measurement. A new laser ablation (LA) in situ sampling technique rapid online 14 C analyses by AMS presented. By focusing a 193-nm ArF excimer on samples, carbon dioxide generated can directly introduced into gas ion source an AMS. dedicated LA cell was...

The 1714 Bhutan earthquake was one of the largest in Himalaya last millennium. We show that surface rupture caused by this extended further to east than previously known, it at least 175 km long, with slip exceeding 11 m our study site. age constrained a combination radiocarbon and traditional optically stimulated luminescence dating affected river sediments. Computations using empirical scaling relationships, fitting historical observations paleoseismic data, yielded plausible magnitude Mw...

Sample introduction of online radiocarbon (¹⁴C) analysis using LA coupled to accelerator mass spectrometry (AMS) has been characterized and optimized.

Abstract Stock assessments for Shovelnose Sturgeon have largely been limited to age and growth analyses using pectoral fin rays despite potential underestimation of lack validation. Fisheries stock rely on accurate estimates vital rates effective fisheries management, within which fish lifespan are primary importance. Age was estimated otolith sections, bomb radiocarbon ( 14 C) dating applied cores determine validate ages. reading straightforward, whereas most thin sections provided two...

ABSTRACT The dating of pollen grains is emerging as the method choice for lacustrine climate archives that contain few datable macrofossils. Due to need high-purity concentrates, new methods are constantly being developed precisely separate grains. Flow cytometry represents a promising alternative conventional approaches, enabling identification through fluorescence and rapid separation radiocarbon analysis using accelerator mass spectrometry, which has so far been limited sediments with...

ABSTRACT Laser ablation (LA) accelerator mass spectrometry (AMS) is a novel method for rapid online radiocarbon ( 14 C) analysis of carbonates. The quasi-continuous C profiles obtained with this technique demand customized data evaluation protocol to relate the acquired analyzed sample. We take into account mixing effects due minimal counting (integration) time AMS, finite width laser beam and gas washout volume. Thereby we mathematically describe our LA setup system function that acts on...

Radiocarbon (14C) is broadly used in oceanography to determine water ages, trace circulation, and develop sediment- sclerochronologies. These applications require an accurate knowledge of marine 14C levels, which have been largely perturbed by human activities. Globally during the last century above-ground nuclear weapon testings primary cause increased atmospheric 14C. However, other anthropogenic sources may caused important regional deviations from bomb pulse. For 70 years European fuel...

Abstract. Rapid and continuous analysis of radiocarbon (14C) concentration in carbonate samples at spatial resolution down to 100 µm has been made possible with the new LA-AMS (laser ablation accelerator mass spectrometry) technique. This novel approach can provide data a similar that stable carbon (C) isotope measurements by ratio spectrometry micromilled and, thus, help interpret δ13C signatures, which otherwise are difficult understand due numerous processes contributing changes C-isotope...

Abstract Age-reading protocols for tuna species using annual growth zones in thin-cut transverse otolith sections have produced greater age estimates than previous methods. Lifespan yellowfin (YFT) and bigeye (BET) (Thunnus albacares T. obesus) were validated up to 16–18 years the western North Atlantic Ocean bomb 14C dating current study extends approach YFT BET of central Pacific (WCPO). Archived otoliths from young-of-the-year (YOY) caught WCPO analysed establish a reference chronology...

In heritage sciences, the ability to obtain information about origin and dating of cultural objects is fundamental for placing an object into its historical context. Radiocarbon (14C) can help identify period during which a work art was created by constitutive materials. Such can, however, only be obtained removing sample from object, critical since irreplaceable demands that sampling kept minimum. this context, we propose novel approach, targets natural organic binder pictorial layer as new...