scholarly journals Comparison of Radiocarbon Ages from Different Organic Fractions in Tropical Peat Cores: Insights from Kalimantan, Indonesia

Radiocarbon ◽  
2008 ◽  
Vol 50 (3) ◽  
pp. 359-372 ◽  
Author(s):  
Raphael A J Wüst ◽  
Geraldine E Jacobsen ◽  
Haitse von der Gaast ◽  
Andrew M Smith
Keyword(s):  
Bulk Sample ◽  
Pollen Extract ◽  
Age Difference ◽  
Tropical Peat ◽  
Peat Deposits ◽  
Extract Fraction ◽  
Organic Fractions ◽  
The Individual ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Various organic fractions of an Indonesian tropical peat deposit were dated using radiocarbon accelerator mass spectrometry (AMS). Four different depth layers, deposited during the last 28,000 14C yr, were analyzed and the data compared to bulk sample analyses. The pollen extracts consistently produced the oldest dates. The bulk samples (<250 μm and <100 μm) often yielded the youngest dates. The age difference between the individual fractions depended on the layer depth and hence the true age of the sampled peats. The age discrepancy was highest (∼16,000 14C yr) in the oldest peat material. We interpret this to be a consequence of the input of organic matter over a long period of time, with peat oxidation and/or no peat accumulation during the last glacial maximum (LGM). The age discrepancies were smaller (between 10 and 900 14C yr) for the Holocene peat samples. It was concluded that the pollen extract fraction might be the most reliable fraction for dating tropical peat deposits that are covered by deeply rooting vegetation.

The onset of deglaciation of Cumberland Bay and Stromness Bay, South Georgia

2005 ◽  
Vol 17 (1) ◽  
pp. 29-32 ◽  
Author(s):  
N. VAN DER PUTTEN ◽  
C. VERBRUGGEN
Keyword(s):  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Aquatic Habitats ◽  
The Holocene ◽  
Carbon Dating ◽  
South Georgia ◽  
Last Glacial ◽  
Peat Deposits ◽  
The Last Glacial Maximum ◽  
The Last Glacial

Carbon dating of basal peat deposits in Cumberland Bay and Stromness Bay and sediments from a lake in Stromness Bay, South Georgia indicates deglaciation at the very beginning of the Holocene before c. 9500 14C yr BP. This post-dates the deglaciation of one local lake which has been ice-free since at least 15 700 14C yr BP on account of its atypical geomorphological location. The latter indicates the likely presence of floristic refugia on South Georgia during the Last Glacial Maximum from which newly exposed terrestrial and aquatic habitats were rapidly colonized.

scholarly journals Late Upper Palaeolithic hunter-gatherers in the Central Mediterranean: new archaeological and genetic data from the Late Epigravettian burial Oriente C (Favignana, Sicily)

2019 ◽  
Author(s):  
Giulio Catalano ◽  
Domenico Lo Vetro ◽  
Pier Francesco Fabbri ◽  
Swapan Mallick ◽  
David Reich ◽  
...  
Keyword(s):  
Upper Palaeolithic ◽  
Central Mediterranean ◽  
Hunter Gatherers ◽  
Radiocarbon Dates ◽  
Late Upper Palaeolithic ◽  
Human Colonization ◽  
The Individual ◽  
The Last Glacial Maximum ◽  
Early Human ◽  
The Last Glacial

AbstractGrotta d’Oriente, a small coastal cave located on the island of Favignana (Sicily, Italy) is a key site for the study of the early human colonization of Sicily. The individual known as Oriente C was found in the lower portion of an anthropogenic deposit containing typical local Late Upper Palaeolithic (Late Epigravettian) stone assemblages. Two radiocarbon dates on charcoal from the deposit containing the burial are consistent with the archaeological context and refer Oriente C to a period spanning about 14,200-13,800 cal. BP. Anatomical features are close to those of Late Upper Palaeolithic populations of the Mediterranean and show strong affinity with Palaeolithic individuals of San Teodoro. Here we present new ancient DNA data from Oriente C. Our results, confirming previous genetic analysis, suggest a substantial genetic homogeneity among Late Epigravettian hunter-gatherer populations of Central Mediterranean, presumably as a consequence of continuous gene flow among different groups, or a range expansion following the Last Glacial Maximum (LGM).

Reconstructions of the past distribution of Testudo graeca mitochondrial lineages in the Middle East and Transcaucasia support multiple refugia since the Last Glacial Maximum

2021 ◽  
pp. 10-17
Author(s):  
Oguz Turkozan
Keyword(s):  
Middle East ◽  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Testudo Graeca ◽  
Last Glacial ◽  
The Past ◽  
Precipitation Seasonality ◽  
Multiple Refugia ◽  
The Last Glacial Maximum ◽  
The Last Glacial

A cycle of glacial and interglacial periods in the Quaternary caused species’ ranges to expand and contract in response to climatic and environmental changes. During interglacial periods, many species expanded their distribution ranges from refugia into higher elevations and latitudes. In the present work, we projected the responses of the five lineages of Testudo graeca in the Middle East and Transcaucasia as the climate shifted from the Last Glacial Maximum (LGM, Mid – Holocene), to the present. Under the past LGM and Mid-Holocene bioclimatic conditions, models predicted relatively more suitable habitats for some of the lineages. The most significant bioclimatic variables in predicting the present and past potential distribution of clades are the precipitation of the warmest quarter for T. g. armeniaca (95.8 %), precipitation seasonality for T. g. buxtoni (85.0 %), minimum temperature of the coldest month for T. g. ibera (75.4 %), precipitation of the coldest quarter for T. g. terrestris (34.1 %), and the mean temperature of the driest quarter for T. g. zarudyni (88.8 %). Since the LGM, we hypothesise that the ranges of lineages have either expanded (T. g. ibera), contracted (T. g. zarudnyi) or remained stable (T. g. terrestris), and for other two taxa (T. g. armeniaca and T. g. buxtoni) the pattern remains unclear. Our analysis predicts multiple refugia for Testudo during the LGM and supports previous hypotheses about high lineage richness in Anatolia resulting from secondary contact.

WASATCH RANGE, UT GLACIER RECONSTRUCTIONS FOR THE LAST GLACIAL MAXIMUM AND LATEGLACIAL

2017 ◽  
Author(s):  
Brendon J. Quirk ◽  
◽  
Jeffrey R. Moore ◽  
Benjamin J. Laabs ◽  
Mitchell A. Plummer ◽  
...  
Keyword(s):  
Last Glacial Maximum ◽  
Glacial Maximum ◽  
Last Glacial ◽  
The Last Glacial Maximum ◽  
The Last Glacial
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