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SAMPLE INFO : UA2085
Sample ID:UA2085
Station ID:Jensen_Palisades_East
Latitude:65.1
Longitude:-153.19997
Datum:NAD83
Sample Type 1:Tephra Fall
Field Lithology:Rhyolite
Text Description:
The only sample of Jensen_Palisades-6 (what it is labelled as in Table 1 of Jensen and others, 2013) and also the only sample collected in the river level peat (Site F) that formed a distinct, traceable unit (see Fig. 4 in Jensen and others, 2013). Creamy yellow in color, up to 1 cm thick, and laterally continuous within organic-rich silt that contains abundant plant macrofossils and peat lenses, grading down to compact peat at river level. Approximately 2 m above river level, and ~1 m above the numerous reworked blebs of tephra that collectively comprise the lowermost tephra beds at the Palisades (i.e. Jensen_Palisades-1 through 5). Glass morphology is almost exclusively thin tricuspate and bubble-walled shards; mineralogy dominated by plagioclase and pyroxene.

References:
The Palisades is a key reference site for the middle Pleistocene of eastern Beringia: new evidence from paleomagnetics and regional tephrostratigraphy

GEOCHEM DATA
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
Jensen_Palisades_East65.1-153.19997Jensen, B. J. L. The Palisades are on the south bank of the Yukon River in Nowitna National Wildlife Refuge, ~70 km downstream of Tanana village. Palisades East forms a heavily gullied, cliff-like exposure that is generally ~40-45 m in height, but ranges from ~25 m high at Site E to ~55-60 m high at Site D. It is difficult to access safely, with many near-vertical exposures and overhanging blocks of frozen sediment that frequently break free into the Yukon River. Location imprecisely georeferenced from Figure 1 in Jensen et al. (2013). Multiple sections were mapped and sampled across Palisades East: Site B1, B2, IB4, F, D1, and D2. See Jensen et al. (2013).The only sample of Jensen_Palisades-6 (what it is labelled as in Table 1 of Jensen and others, 2013) and also the only sample collected in the river level peat (Site F) that formed a distinct, traceable unit (see Fig. 4 in Jensen and others, 2013). Creamy yellow in color, up to 1 cm thick, and laterally continuous within organic-rich silt that contains abundant plant macrofossils and peat lenses, grading down to compact peat at river level. Approximately 2 m above river level, and ~1 m above the numerous reworked blebs of tephra that collectively comprise the lowermost tephra beds at the Palisades (i.e. Jensen_Palisades-1 through 5). Glass morphology is almost exclusively thin tricuspate and bubble-walled shards; mineralogy dominated by plagioclase and pyroxene.UA2085Tephra FallCumulateGlass 71.05 0.43 14.49 3.27 0.12 0.38 1.58 5.26 3.21 9361EMP3.27Cl=0.22; H2O=5.58EMP

SAMPLE LOCATION

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