A thin (<1 cm), phenocryst-rich tephra, characterized by abundant frothy pumice shards, is present 18 m above river level; upper and lower contacts are sharp and locally undulatory with several cm of relief. The tephra bed hosts very thin whisps of tan silt.
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
|StationID||Latitude||Longitude||Geologist||DateVisited||Age Info||Volcano||Eruption||Location Description||Text Description||Sample ID||Sample Type 1||Sample Type 2||Final Unit||Material||Coeff||SiO2||TiO2||Al2O3||FeOT||MnO||MgO||CaO||Na2O||K2O||P2O5||Total-majors||REF majors||METH majors||Fe2O3/Fe203T orig||FeO/FeOT orig||Volatiles csv||METH volatiles||Cs||Rb||Ba||Sr||La||Ce||Pr||Nd||Sm||Eu||Gd||Tb||Dy||Ho||Er||Tm||Yb||Lu||Y||Zr||Nb||Hf||Ta||Pb||Th||U||Sc||V||Cr||Fe||Co||Ni||Cu||Zn||Ga||Mo||As||Na||K||Ref trace1||METH trace1||Rb||Ba||Sr||La||Ce||Nd||Sm||Eu||Gd||Dy||Er||Yb||Lu||Y||Zr||Nb||Pb||Th||U||Sc||Ti||V||Cr||Ni||Cu||Zn||Ga||Ref trace2||METH trace2||Light csv||Halogen csv||other major csv||other lile csv||other ree csv||other hfse csv||other hpe csv||other tm csv||other misc csv|
|Palisades_Site_A||65.1||-153.41997||Jensen, B. J. L.||0000-00-00||190000 ± 20000 known unit; 2166; Age is approximate.||-188050--||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).||A thin (<1 cm), phenocryst-rich tephra, characterized by abundant frothy pumice shards, is present 18 m above river level; upper and lower contacts are sharp and locally undulatory with several cm of relief. The tephra bed hosts very thin whisps of tan silt.||UA1297||Tephra Fall||Cumulate||Glass||71.92||0.26||15.87||1.89||0.05||0.68||2.76||4.59||1.95||8083||EMP||1.89||Cl=0.03; H2O=3.85||EMP|
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