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SAMPLE INFO : UT816
Sample ID:UT816
Station ID:Halfway_House
Latitude:64.735
Longitude:-148.4594
Datum:NAD83
Sample Type 1:Tephra Fall
Text Description:
UT817 and UT816 form a layered tephra 1.5 m higher than the underlying SD tephra of Preece et al. (1999). It is as thick as 5 cm and, with a discontinuous basal white bed (UT816, 2.5Y8/1)that has a diffuse contact with the overlying gray unit and reworked gray tephra (UT817, ~2.5Y6/1). The tephra is interbedded with massive gray (5Y6/2) silt with small oxidation blebs and occurs in pods with sharp and irregular lower contacts with the underlying silt and diffuse contacts with the overlying loess. However, the white-gray contact is sharp in some areas and the two are separated in places. The average pod thickness is 3 to 5 cm.

References:
Tephrostratigraphy of the late Cenozoic Gold Hill loess, Fairbanks area, Alaska
Tephrochronology of late Cenozoic loess at Fairbanks, central Alaska
Late Pliocene Dawson Cut forest bed and new tephrochronological findings in the Gold Hill Loess, east-central Alaska

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
Halfway_House64.735-148.4594Preece, S. J.< 124000 ± 10000 stratigraphy; 10271; Weighted mean of four Old Crow Tephra sample glass fission-track ages. This tephra is stratigraphically above the Old Crow tephra at this location and is therefore younger.Halfway House site: a 12-m-thick section of the Gold Hill Loess located on top of a rounded bedrock hill along the north side of the Parks Highway, ~50 km west of Fairbanks, Alaska. The exposure was created during construction of the George Parks Highway in the 1960s and is mostly comprised of the Goldstream Formation. Location coordinates from Preece and others (2011); coordinates vary slightly from those reported in Jensen and others (2011). Datum not specified, assumed to be NAD83.UT817 and UT816 form a layered tephra 1.5 m higher than the underlying SD tephra of Preece et al. (1999). It is as thick as 5 cm and, with a discontinuous basal white bed (UT816, 2.5Y8/1)that has a diffuse contact with the overlying gray unit and reworked gray tephra (UT817, ~2.5Y6/1). The tephra is interbedded with massive gray (5Y6/2) silt with small oxidation blebs and occurs in pods with sharp and irregular lower contacts with the underlying silt and diffuse contacts with the overlying loess. However, the white-gray contact is sharp in some areas and the two are separated in places. The average pod thickness is 3 to 5 cm.UT816Tephra FallCumulateGlass 74.36 0.4 14.41 2.54 0.2 0.26 1.89 4.33 1.85 94.9656EMP2.54Cl=0.15EMP 1.24 30 577 209 11.57 28.9 20.7 5.44 1.45 0.99 4.86 0.79 3.38 0.24 2.37 0.87 15.1 2.4 79 56INAA

SAMPLE LOCATION

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