AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > 87-APH

SAMPLE INFO : 87-APH
Sample ID:87-APH
Station ID:87-APH
Latitude:65.1
Longitude:-153.29997
Datum:NAD83
Sample Type 1:Tephra Fall
 Text Description:
5 to 20-cm-thick volcanic ash layer extending for more than 40 m across the central cliff face. The tephra lies 15 to 20 m below the top of the cliff and about 4 to 5 m below a prominent organic horizon that could also be traced across much of the cliff face. The tephra itself is cross-bedded, and may also have been slightly reworked, although it forms a subhorizontal and essentially continuous horizon as much as 20 cm thick, and occurs in homogeneous silts (see Figure 3 in Beget et al. 1991). The layer of tephra is overlain by 60 cm of light gray to pale brown blocky silt containing a few stringers of tephra. Consists largely of platey clear glass shards composed of fragments of bubble walls and junctions.

References:
Old Crow Tephra found at the Palisades of the Yukon, Alaska
The Stampede Tephra: a middle Pleistocene marker bed in glacial and eolian deposits of central Alaska
Late Pleistocene environments of the western Noatak basin, northwestern 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
87-APH65.1-153.29997Beget, J. E. Palisades along the Yukon River; the Palisades are bluffs or cliffs as much as 90 m high along 11 km of the south bank of the Yukon River near Tanana, Alaska. Much of the extensive bluff is underlain by Tertiary sedimentary rocks and lignite, but Quaternary sediments capping the bluff are locally as much as 60 m thick (Yeend, 1977). Location imprecisely georeferenced from Figure 1 of Beget et al. (1991).5 to 20-cm-thick volcanic ash layer extending for more than 40 m across the central cliff face. The tephra lies 15 to 20 m below the top of the cliff and about 4 to 5 m below a prominent organic horizon that could also be traced across much of the cliff face. The tephra itself is cross-bedded, and may also have been slightly reworked, although it forms a subhorizontal and essentially continuous horizon as much as 20 cm thick, and occurs in homogeneous silts (see Figure 3 in Beget et al. 1991). The layer of tephra is overlain by 60 cm of light gray to pale brown blocky silt containing a few stringers of tephra. Consists largely of platey clear glass shards composed of fragments of bubble walls and junctions. 87-APHTephra FallCumulateGlass 75.36 0.29 13.1 1.84 0.28 1.44 3.72 3.68 1525EMP1.84Cl=0.29EMP

SAMPLE LOCATION

Contact AVO Privacy Accessibility Information Quality FOIA
URL: 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 G22AC00137

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