AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > 87-WAD-3

SAMPLE INFO : 87-WAD-3
Sample ID:87-WAD-3
Station ID:87-WAD-3
Latitude:62.1586
Longitude:-144.4073
Datum:NAD83
Date Sampled:1987-00-00
Sample Type 1:Lava
Sample Type 2:Flow
Field Lithology:Andesite
Sample Unit:Qwa
Text Description:
Mount Wrangell two-pyroxene andesite flows (Pleistocene). Extensive, medium- to dark-gray, thin to thick (5-30 m) flows that generally exhibit oxidized and slightly scoriaceous tops and bottoms. In places, unit contains lenses of light-colored silicic airfall tuff. Rock is conspicuously porphyritic, containing phenocrysts of plagioclase (10-24%, 1-10mm), hypersthene (1-8%, 0.5-3 mm), augite (trace to 3%, 1-4 mm), and olivine (trace), in intersertal to pilotaxitic groundmass of plagioclase, mafic minerals, and brown glass. Hypersthene is invariably the dominant phenocrystic pyroxene. * * * Plagioclase from two samples (locs. 6, 9, table 1) yielded K-Ar ages of 0.60+/-0.02 and 0.51 +/-0.02 M, respectively. Most likely source is summit region of Wrangell volcano, but unit may also include flows from Wrangell flank eruptions or from older Chetaslina eruptive center 5 km south of quadrangle, especially in area of Chichokna and Chetaslina Glaciers. * * * Maximum thickness probably more than 400 m.

References:
Geologic map of the Gulkana A-1 Quadrangle, south-central Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedVolcanoLocation DescriptionText DescriptionSample IDSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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-WAD-3 62.1586 -144.4073 Unknown, Unknown 1987-00-00 WrangellMount Wrangell rocks within Gulkana A-1 quadrangle. Latitude and longitude derived from paper map.Mount Wrangell two-pyroxene andesite flows (Pleistocene). Extensive, medium- to dark-gray, thin to thick (5-30 m) flows that generally exhibit oxidized and slightly scoriaceous tops and bottoms. In places, unit contains lenses of light-colored silicic airfall tuff. Rock is conspicuously porphyritic, containing phenocrysts of plagioclase (10-24%, 1-10mm), hypersthene (1-8%, 0.5-3 mm), augite (trace to 3%, 1-4 mm), and olivine (trace), in intersertal to pilotaxitic groundmass of plagioclase, mafic minerals, and brown glass. Hypersthene is invariably the dominant phenocrystic pyroxene. * * * Plagioclase from two samples (locs. 6, 9, table 1) yielded K-Ar ages of 0.60+/-0.02 and 0.51 +/-0.02 M, respectively. Most likely source is summit region of Wrangell volcano, but unit may also include flows from Wrangell flank eruptions or from older Chetaslina eruptive center 5 km south of quadrangle, especially in area of Chichokna and Chetaslina Glaciers. * * * Maximum thickness probably more than 400 m.87-WAD-3 59.770355663552 0.96436204095814 16.675426958235 5.5126108619552 0.12054525511977 3.616357653593 6.067444507695 3.7369029087128 2.1999509059358 0.22099963438624 99.712262NN1.624.03H2OP=0.78; H2OM=0.27; CO2=0.06RAPIDA

SAMPLE LOCATION

Contact AVO Privacy Accessibility Information Quality FOIA
URL: www.avo.alaska.edu/samples/sample_info.php
Page modified: July 14, 2014 13:37
Contact Information: AVO Web Team

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