AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > UT114

SAMPLE INFO : UT114
Sample ID:UT114
Station ID:UT114
Latitude:66.53
Longitude:-152.08
Datum:NAD83
Sample Type 1:Tephra Fall
Text Description:
Old Crow tephra is preserved near the base of bedded silt that probably originated as loess but was deposited or redeposited in standing water. Laminations indicate that the tephra has been reworked; a single 5-cm-thick bed is covered by thin couplets of nearly pure tephra and gray silt, the combined thickness of the tephra-rich zone being 30 cm. A peaty bed with spruce fragments and a loess bed overlie the tephra-bearing silt, beneath which glacial drift of Kobuk and earlier glaciations is exposed (See Fig. 7 in Westgate et al. 1983).

References:
Old Crow tephra: a new late Pleistocene stratigraphic marker across North-central Alaska and western Yukon Territory
Discovery of a large-magnitude, late Pleistocene volcanic eruption in Alaska
Correlation techniques in tephra studies

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
UT11466.53-152.08Westgate, J. A. 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).Exposure 11 of Westgate et al. (1983), along the Koyokuk River, northern Alaska near the Brooks Range. Lies within the Alatna River lobe of the Kobuk-age glacier complex (See Fig. 6 in Westgate et al. 1983). The sedimentary sequence is illustrated in Figure 7 (of Westgate et al. 1983). It is likely that nearly continuous deposition of aeolian, lacustrine, and perhaps fluvial silt took place in this area during the Itkillik and Walker Lake ice advances.Old Crow tephra is preserved near the base of bedded silt that probably originated as loess but was deposited or redeposited in standing water. Laminations indicate that the tephra has been reworked; a single 5-cm-thick bed is covered by thin couplets of nearly pure tephra and gray silt, the combined thickness of the tephra-rich zone being 30 cm. A peaty bed with spruce fragments and a loess bed overlie the tephra-bearing silt, beneath which glacial drift of Kobuk and earlier glaciations is exposed (See Fig. 7 in Westgate et al. 1983).UT114Tephra FallCumulateGlass 74.95 0.28 13.39 1.73 0.33 1.44 3.7 3.69 1792EMP: SiO2, TiO2, Al2O3, FeOT, MgO, CaO, K2O; INAA: Na2O; 1.791.73Cl=0.25; H2O=6.3EMP 84 23 50 27 5.5 0.8 0.93 1.3 3.5 3.1 0.38 6.2 0.65 8.9 3.5 6.5 6 1237INAA
UT11466.53-152.08Westgate, J. A. 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).Exposure 11 of Westgate et al. (1983), along the Koyokuk River, northern Alaska near the Brooks Range. Lies within the Alatna River lobe of the Kobuk-age glacier complex (See Fig. 6 in Westgate et al. 1983). The sedimentary sequence is illustrated in Figure 7 (of Westgate et al. 1983). It is likely that nearly continuous deposition of aeolian, lacustrine, and perhaps fluvial silt took place in this area during the Itkillik and Walker Lake ice advances.Old Crow tephra is preserved near the base of bedded silt that probably originated as loess but was deposited or redeposited in standing water. Laminations indicate that the tephra has been reworked; a single 5-cm-thick bed is covered by thin couplets of nearly pure tephra and gray silt, the combined thickness of the tephra-rich zone being 30 cm. A peaty bed with spruce fragments and a loess bed overlie the tephra-bearing silt, beneath which glacial drift of Kobuk and earlier glaciations is exposed (See Fig. 7 in Westgate et al. 1983).UT114Tephra FallCumulateGlassUnclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 73.63Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 0.35Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 13.54 Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 0.04Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 0.44Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 1.77Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 3.77Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 3.8Unclear if averages are reported or if data are individual points of analysis. Standard deviation not reported. 0.11 1126EMP2.54 23 50 26 5.5 0.9 0.93 1.3 3.1 0.38 6 0.7 5.1 3.5 6.5 1183INAA
UT11466.53-152.08Westgate, J. A. 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).Exposure 11 of Westgate et al. (1983), along the Koyokuk River, northern Alaska near the Brooks Range. Lies within the Alatna River lobe of the Kobuk-age glacier complex (See Fig. 6 in Westgate et al. 1983). The sedimentary sequence is illustrated in Figure 7 (of Westgate et al. 1983). It is likely that nearly continuous deposition of aeolian, lacustrine, and perhaps fluvial silt took place in this area during the Itkillik and Walker Lake ice advances.Old Crow tephra is preserved near the base of bedded silt that probably originated as loess but was deposited or redeposited in standing water. Laminations indicate that the tephra has been reworked; a single 5-cm-thick bed is covered by thin couplets of nearly pure tephra and gray silt, the combined thickness of the tephra-rich zone being 30 cm. A peaty bed with spruce fragments and a loess bed overlie the tephra-bearing silt, beneath which glacial drift of Kobuk and earlier glaciations is exposed (See Fig. 7 in Westgate et al. 1983).UT114Tephra FallCumulateGlass 23 50 26 5.5 0.9 0.93 1.3 3.1 0.38 6 0.7 5.1 3.5 6.5 6 1126INAA
UT11466.53-152.08Westgate, J. A. 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).Exposure 11 of Westgate et al. (1983), along the Koyokuk River, northern Alaska near the Brooks Range. Lies within the Alatna River lobe of the Kobuk-age glacier complex (See Fig. 6 in Westgate et al. 1983). The sedimentary sequence is illustrated in Figure 7 (of Westgate et al. 1983). It is likely that nearly continuous deposition of aeolian, lacustrine, and perhaps fluvial silt took place in this area during the Itkillik and Walker Lake ice advances.Old Crow tephra is preserved near the base of bedded silt that probably originated as loess but was deposited or redeposited in standing water. Laminations indicate that the tephra has been reworked; a single 5-cm-thick bed is covered by thin couplets of nearly pure tephra and gray silt, the combined thickness of the tephra-rich zone being 30 cm. A peaty bed with spruce fragments and a loess bed overlie the tephra-bearing silt, beneath which glacial drift of Kobuk and earlier glaciations is exposed (See Fig. 7 in Westgate et al. 1983).UT114Tephra FallCumulateGlass 3.7 1000 25.3 48.6 28 5.61 0.9 1 3.5 0.64 7.1 0.9 9.3 4.4 6.7 1792INAA

SAMPLE LOCATION

Contact AVO Privacy Accessibility Information Quality FOIA
URL: www.avo.alaska.edu/samples/sample_info.php
Page modified: August 1, 2017 15:29
Contact Information: AVO Web Team

twitter @alaska_avo
facebook alaska.avo
email Receive volcano updates by email: USGS VNS

This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G19AC00060 and G19AC00171.

Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.