Subseasonal variations in marine reservoir age from pre-bomb Donax obesulus and Protothaca asperrima shell carbonate

AbstractRa’s al-Hamra 6 (RH-6) is one of the earliest stratified archaeological sites along the eastern littoral of the Arabian Peninsula. This shell midden was radiocarbon dated to the 6th–5th millennium cal BC, but the majority of the dates were obtained before the advent of accelerator mass spectrometry (AMS) 14C dating and suffer from large uncertainties. In addition, most of these dates were obtained on marine and mangrove shells and required correction for local variations from the global average marine 14C reservoir age (MRA). This proved difficult because no consensus value exists for this period in the area. Recent excavations at RH-6 offered the opportunity to redate this important site in order to precisely determine its occupation history and later use as a graveyard, and establish the marine reservoir effect for this time period. Thirty-eight samples of charcoal, shells, and human bone apatite were selected for 14C dating. Bayesian modeling of the 14C dates suggests that the formation of the shell midden spanned ~1 millennium, between the mid-6th and the mid-5th millennium cal BC. Positive and consistent ΔR values were calculated throughout the entire sequence, ranging from 99±27 to 207±43 14C yr. At the beginning of the 4th millennium cal BC, RH-6 was used as a graveyard, as suggested by the 14C dating of a shell in strict association with an individual buried at the surface of the site. 14C dating of human bone apatite allowed us to calculate that 89% of this individual’s diet derived from marine resources. This finding confirms previous observations showing the overwhelming presence of marine and mangrove-dwelling species in the faunal and charcoal assemblage, and implies a low mobility, or mobility restricted to the coast for this population during the 4th millennium cal BC.

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Refinement of the open ocean reservoir age in the North Atlantic-Norwegian Sea using Icelandic historical tephra layers (the last 1100 years)

Quaternary International ◽

10.1016/j.quaint.2012.08.292 ◽

2012 ◽

Vol 279-280 ◽

pp. 184

Author(s):

Haflidi Haflidason

Keyword(s):

North Atlantic ◽

Open Ocean ◽

Norwegian Sea ◽

The North ◽

Tephra Layers ◽

The North Atlantic ◽

Reservoir Age

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On Correcting 14C Ages of Gastropod Shell Carbonate for Fractionation

Radiocarbon ◽

10.1017/s0033822200032203 ◽

2002 ◽

Vol 44 (3) ◽

pp. 755-760 ◽

Cited By ~ 13

Author(s):

Jeffrey S Pigati

Keyword(s):

Isotopic Composition ◽

Carbon Isotopic Composition ◽

Iterative Approach ◽

Shell Formation ◽

Gastropod Shell ◽

Carbon Isotopic ◽

Soil Carbonate ◽

Shell Carbonate ◽

Atmospheric Carbon

Correcting the 14C age of a sample for fractionation is straightforward if the measured carbon was derived entirely from the atmosphere, either directly or through chemical and/or biological reactions that originated with atmospheric carbon. This correction is complicated in the case of gastropods that incorporate carbon from limestone or secondary carbonate (e.g. soil carbonate) during shell formation. The carbon isotopic composition of such gastropod shells is determined by fractionation, as well as mixing of carbon from sources with different isotopic values. Only the component of shell carbonate derived from atmospheric carbon should be corrected for fractionation. In this paper, the author derives a new expression for correcting the measured 14C activity of gastropod shells for fractionation, and describe an iterative approach that allows the corrected 14C activity and the fraction of shell carbonate derived from atmospheric carbon to be determined simultaneously.

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Aminostratigraphic Correlation and Geochronology of Two Quaternary Loess Localities, Central Mississippi Valley

Quaternary Research ◽

10.1006/qres.1994.1033 ◽

1994 ◽

Vol 41 (3) ◽

pp. 289-297 ◽

Cited By ~ 16

Author(s):

June E. Mirecki ◽

Barry B. Miller

Keyword(s):

Amino Acid ◽

Kinetic Model ◽

Mississippi Valley ◽

River Section ◽

Mollusc Shell ◽

The Third ◽

Shell Carbonate ◽

Parabolic Kinetic

AbstractAmino acid epimeric (aIle/Ile) values from terrestrial molluscs are used to define and correlate three aminozones in loess sequences exposed across the central Mississippi Valley, in Arkansas and Tennessee. Three superposed aminozones are defined at Wittsburg quarry, Arkansas, primarily using aIle/Ile values from total hydrolysates of the gastropod genus Hendersonia: Peoria Loess (aIle/Ile = 0.07 ± 0.01), Roxana Silt (0.14 ± 0.02), and a third loess (0.28 ± 0.06). Loess units at Wittsburg quarry can be correlated on lithologic characteristics eastward across the Mississippi Valley to the Old River section, near Memphis, Tennessee; however, only one loess unit is fossil-bearing (Peoria Loess, aIle/Ile = 0.05) at that section. Radiocarbon analyses of charcoal from the upper Roxana Silt (ca. 26,000 to 29,000 yr old) and mollusc shell carbonate from the basal Roxana Silt (ca. 39,000 yr old) are used to calibrate amino acid epimeric data for the central Mississippi Valley. These data, applied to the apparent parabolic kinetic model of R. M. Mitterer and N. Kriausakul (1989, Quaternary Science Reviews 8, 353-357), suggest an Illinoian (>120,000 yr) age for the third loess in the central Mississippi Valley that is correlative with part of the Loveland Loess in Illinois and Iowa.

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14C age anomalies in modern land snails shell carbonate from Southern Italy

Quaternary Geochronology ◽

10.1016/j.quageo.2007.01.006 ◽

2008 ◽

Vol 3 (1-2) ◽

pp. 68-75 ◽

Cited By ~ 33

Author(s):

Lea Romaniello ◽

Gianluca Quarta ◽

Giuseppe Mastronuzzi ◽

Marisa D’Elia ◽

Lucio Calcagnile

Keyword(s):

Southern Italy ◽

Land Snails ◽

14C Age ◽

Shell Carbonate

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The 3.6 ka Aniakchak tephra in the Arctic Ocean: a constraint on the Holocene radiocarbon reservoir age in the Chukchi Sea, a review

10.5194/cp-2016-112-rc3 ◽

2017 ◽

Author(s):

Anonymous

Keyword(s):

Arctic Ocean ◽

Chukchi Sea ◽

The Arctic ◽

The Holocene ◽

The Arctic Ocean ◽

Reservoir Age

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Lake water dissolved inorganic carbon dynamics revealed from monthly measurements of radiocarbon in the Fuji Five Lakes, Japan

Elem Sci Anth ◽

10.1525/elementa.2020.00149 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Kosuke Ota ◽

Yusuke Yokoyama ◽

Yosuke Miyairi ◽

Shinya Yamamoto ◽

Toshihiro Miyajima

Keyword(s):

Lake Water ◽

Inorganic Carbon ◽

Environmental Changes ◽

Dissolved Inorganic Carbon ◽

Anthropogenic Activities ◽

Aquatic Organisms ◽

Human Society ◽

History Of ◽

Lake Waters ◽

Reservoir Age

Lakes are sensitive recorders of anthropogenic activities, as human society often develops in their vicinity. Lake sediments thus have been widely used to reconstruct the history of environmental changes in the past, anthropogenic, or otherwise, and radiocarbon dating provides chronological control of the samples. However, specific values of radiocarbon in different carbon reservoirs due to the different pathways of radiocarbon from the upper atmosphere to the lake, called the radiocarbon reservoir age, is always difficult to evaluate because of dynamic processes in and around lakes. There are few systematic studies on radiocarbon reservoir ages for lakes owing to the complex radiocarbon transfer processes for lakes. Here, we investigate lake waters of the Fuji Five Lakes with monthly monitoring of the radiocarbon reservoir effects. Radiocarbon from dissolved inorganic carbon (DIC) for groundwater and river water is also measured, with resulting concentrations (Δ14C) at their lowest at Lake Kawaguchi in August 2018 (–122.4 ± 3.2‰), and at their highest at Lake Motosu in January 2019 (–22.4 ± 2.5‰), despite a distance of 25 km. However, winter values in both lakes show similar trends of rising Δ14C (about 20‰). Our lake water DIC Δ14C results are compared to previously published records obtained from sediments in Lake Motosu and Lake Kawaguchi. These suggest that total organic carbon and compound-specific radiocarbon found in sediments are heavily influenced by summer blooms of aquatic organisms that fix DIC in water. Thus, future studies to conduct similar analyses at the various lakes would be able to provide further insights into the carbon cycle around inland water, namely understanding the nature of radiocarbon reservoir ages.

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