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Sample ID:UA1423
Station ID:Palisades_Site_A
Sample Type 1:Tephra Fall
Text Description:
Site A1. Tephra bed up to 2.5 cm thick. Massive grey silt overlies this tephra at Site A1.

A late-Middle Pleistocene (Marine Isotope Stage 6) vegetated surface buried by Old Crow tephra at the Palisades, interior Alaska
The Palisades is a key reference site for the middle Pleistocene of eastern Beringia: new evidence from paleomagnetics and regional tephrostratigraphy

StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDSample Type 1Sample Type 2Final UnitMaterialCoeffSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-majorsREF majorsMETH majorsFe2O3/Fe203T origFeO/FeOT origVolatiles csvMETH volatilesCsRbBaSrLaCePrNdSmEuGdTbDyHoErTmYbLuYZrNbHfTaPbThUScVCrFeCoNiCuZnGaMoAsNaKRef trace1METH trace1RbBaSrLaCeNdSmEuGdDyErYbLuYZrNbPbThUScTiVCrNiCuZnGaRef trace2METH trace2Light csvHalogen csvother major csvother lile csvother ree csvother hfse csvother hpe csvother tm csvother misc csv
Palisades_Site_A65.1-153.41997Jensen, B. J. L.0000-00-00 124000 ± 10000 known unit; 10271; Age is approximate. Revised glass fission-track age with re-calibration; four Old Crow Tephra sample glass fission-track ages (UT1434, UT613, UT501, UT613).North-facing river-cut exposures on the Yukon River in Alaska about 70 km downstream of the village of Tanana. Site A at Palisades West is less than 30 m high and partially covered by willow thickets. From river level, a thick white tephra is visible across the top of exposure. The lowermost 16 m consist of massive and stratified sand and gravel, with one thin bed of laminated silt. A sharp contact separates these sediments from ~10 m of massive-to-faintly laminated tan/grey silt with thin, diffuse organic beds. Uppermost several metres of Site A sediments measured at three different sections. Location imprecisely georeferenced from Figure 1 of Reyes et al. (2010).Site A1. Tephra bed up to 2.5 cm thick. Massive grey silt overlies this tephra at Site A1.UA1423Tephra FallCumulateGlass 75.51 0.29 13.05 1.75 0.07 0.29 1.45 3.68 3.67 8083EMP1.75Cl=0.25; H2O=4.46EMP


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