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SAMPLE INFO : 96TOK1-9
Sample ID:96TOK1-9
Station ID:96TOK1
Latitude:63.198
Longitude:-142.178
Datum:NAD83
Sample Type 1:Tephra Fall
Text Description:
4- to 16-cm thick tephra; white with black mafics. Highly vesicular pumice with an average grain size of 250 microns. Collected from within the top 1 meter of Unit 6, which consists of organic-rich, black-gray silt. Within the silt are 1- to 3-cm-thick, organic-rich bands and fine laminations of silt and tephra. This tephra is the thickest and most coarse-grained tephra in the section; it occurs as 4- to 16-cm-thick lenses within organic-rich silt up to 30 cm below tephra 96TOK1-12. Salt-and-pepper in color. Thickest, cleanest sample of this lower, coarse, pumiceous, hornblende-rich tephra was collected for Ar/Ar analysis.

References:
Stratigraphy, major oxide geochemistry, and 40Ar/39Ar geochronology of a tephra section near Tok, 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
96TOK163.198-142.178Schaefer, J. R. G.0000-00-00 627500 ± 47700 40Ar/39Ar; 3668; Age is approximate. Several runs of single-step laser fusion 40Ar/39Ar dating of multiple grains of low K hornblede in tephra sample.-625550--Road-cut at mile 1284.6 of the Alaska Highway, southeast of Tok, Alaska. Approximately 17 miles east of Tetlin Junction and 100 miles north of Wrangell volcanic field. Twelve-m-thick section that exposes interbedded sands, silt and tephra that were deposited against a southeasterly sloping, highly weathered intrusive rock. The section is divided into six units based on lithology. Ten tephra samples were taken; however, approximately one m below tephra 96TOK1-9, there are wispy layers of several multiple-banded tephras that were very thin and discontinuous and not detailed in Schaefer (2002). Datum not specified, assumed to be NAD83. 4- to 16-cm thick tephra; white with black mafics. Highly vesicular pumice with an average grain size of 250 microns. Collected from within the top 1 meter of Unit 6, which consists of organic-rich, black-gray silt. Within the silt are 1- to 3-cm-thick, organic-rich bands and fine laminations of silt and tephra. This tephra is the thickest and most coarse-grained tephra in the section; it occurs as 4- to 16-cm-thick lenses within organic-rich silt up to 30 cm below tephra 96TOK1-12. Salt-and-pepper in color. Thickest, cleanest sample of this lower, coarse, pumiceous, hornblende-rich tephra was collected for Ar/Ar analysis.96TOK1-9Tephra FallCumulateGlass 75.51 0.23 13.83 0.35 1.59 4.09 3.11 Reported standard deviation of zero. 1003668EMP1.23Cl=0.05EMP

SAMPLE LOCATION

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