Tephrochronology, magnetostratigraphy and mammalian faunas of Middle and Early Pleistocene sediments at two sites on the Old Crow River, northern Yukon Territory, Canada

  title={Tephrochronology, magnetostratigraphy and mammalian faunas of Middle and Early Pleistocene sediments at two sites on the Old Crow River, northern Yukon Territory, Canada},
  author={John A. Westgate and G. William Pearce and Shari J. Preece and Charles Earl Schweger and Richard E. Morlan and Nicholas J. G. Pearce and T. William Perkins},
  journal={Quaternary Research},
  pages={75 - 85}
Abstract Alluvial and lacustrine sediments exposed beneath late Pleistocene glaciolacustrine silt and clay at two sites along the Old Crow River, northern Yukon Territory, are rich in fossils and contain tephra beds. Surprise Creek tephra (SZt) occurs in the lower part of the alluvial sequence at CRH47 and Little Timber tephra (LTt) is present near the base of the exposure at CRH94. Surprise Creek tephra has a glass fission-track age of 0.17 ± 0.07 Ma and Little Timber tephra is 1.37 ± 0.12 Ma… 
Age of some Pleistocene interglacial beds and associated fossils in eastern Beringia defined by fission tracks in glass shards of Chester Bluff tephra
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The Palisades is a key reference site for the middle Pleistocene of eastern Beringia: new evidence from paleomagnetics and regional tephrostratigraphy
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Middle Pleistocene (MIS 7) to Holocene fossil insect assemblages from the Old Crow basin, northern Yukon, Canada
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Rift flank uplift and landscape evolution of Hall Peninsula , Baffin Island , Nunavut : an exhumation model based on low-temperature thermochronology
This study is part of the Canada-Nunavut Geoscience Office’s Hall Peninsula Integrated Geoscience Program, a multiyear bedrock and surficial geology mapping program with associated thematic studies.
First Fossils of Hyenas (Chasmaporthetes, Hyaenidae, Carnivora) from North of the Arctic Circle
The northern region of Beringia is ecologically and biogeographically significant as a corridor for biotic dispersals between the Old and New Worlds. Large mammalian predators from Beringia are
Mammuthus Population Dynamics in Late Pleistocene North America: Divergence, Phylogeography, and Introgression
It is hypothesized that at least two distinct stages of interbreeding between conventional paleontological species are likely responsible for this pattern – one between Siberian woolly mammoths and resident American populations that introduced woolly mammoth phenotypes to the continent, and another between ecomorphologically distinct populations of woolly and Columbian mammoths in North America south of the ice.
Correlating tephras and cryptotephras using glass compositional analyses and numerical and statistical methods: review and evaluation
Abstract We define tephras and cryptotephras and their components (mainly ash-sized particles of glass ± crystals in distal deposits) and summarize the basis of tephrochronology as a
Million-year-old DNA sheds light on the genomic history of mammoths
It is shown that the majority of protein-coding changes associated with cold adaptation in woolly mammoths were already present one million years ago, highlighting the potential of deep-time palaeogenomics to expand the understanding of speciation and long-term adaptive evolution.


Old Crow tephra: A new late Pleistocene stratigraphic marker across north-central Alaska and western Yukon Territory
Old Crow tephra is the first extensive Pleistocene tephra unit to be documented in the northwestern part of North America. It has a calc-alkaline dacitic composition with abundant pyroxene,
Old Crow tephra across eastern Beringia: a single cataclysmic eruption at the close of Marine Isotope Stage 6
Abstract Old Crow tephra is the largest and most widespread Quaternary eruption presently known in eastern Beringia. Its major- and trace-element geochemistry, Fe-Ti oxides, and stratigraphic and
An extensive middle to late Pleistocene tephrochronologic record from east-central Alaska
Abstract Chester Bluff (CB), in Yukon Charley Rivers National Preserve (YCNP), Alaska, contains an extensive middle to late Pleistocene tephra record within thick loess deposited on a terrace. The
A late-Middle Pleistocene (Marine Isotope Stage 6) vegetated surface buried by Old Crow tephra at the Palisades, interior Alaska
Abstract A 40 cm thick primary bed of Old Crow tephra (131 ± 11 ka), an important stratigraphic marker in eastern Beringia, directly overlies a vegetated surface at Palisades West, on the Yukon River
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Nineteen distinctive, distal tephra beds from the Gold Hill Loess in the Fairbanks region, central Alaska, are divided into two groups based on their color, mineralogy, glass-shard morphology, and
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Wascana Creek Ash, located close to Regina in Saskatchewan, is correlated with Pearlette ash, type O (classification of Izett et al. 1972) on the basis of its mineral assemblage, shard habit,
Fission-track ages of late Cenozoic distal tephra beds in the Yukon Territory and Alaska.
Six distal tephra beds from the Yukon Territory and Alaska have been dated by the fission-track method. Zircon and glass ages were determined for the Fort Selkirk and Lost Chicken tephra beds, but
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The Old Crow Plain, northern Yukon Territory, Canada, is a large flat lowland consisting of basin-fill sediments of Late Quaternary age, and much of the vegetation consists of tundra and shrub tundr, with scattered groves of spruce mainly on alluvial deposits.
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We synthesize pollen spectra from eleven dated stratigraphic sections from central and northern Yukon. Palaeomagnetic and tephra dating indicates the earliest assemblages, representing closed canopy
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