AVO Logo
Site Map | FAQ |
Alaska Volcano Observatory
 
You are here: Home > Samples > Snyder_1959_3

SAMPLE INFO : Snyder_1959_3
Sample ID:Snyder_1959_3
Station ID:Snyder_1959_3
Latitude:51.9531
Longitude:178.5356
Datum:NAD83
Sample Type 1:Lava
Field Lithology:Andesite
Text Description:
Andesite of Little Sitkin dacite. Color: medium gray (N 5). Texture: hypocrystalline, porphyritic with feldspar phenocrysts as much as 4 mm in diameter, and pyroxene phenocrysts as much as 3 mm long. Plagioclase megaphenocrysts, 20-30 percent, range from An35 to An56 and average An47; complex zoning and twinning common. Clinopyroxene, 8 percent, contains rare centers of orthopyroxene, 1 percent. Both unreacted olivine, 5 percent, and pyroxene are stained amber along joints. Magnetite, 2 percent, as anhedrons. Average composition of feldspar microlites in trachytic groundmass is An42.

References:
Geology of Little Sitkin Island, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDMaterialSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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
Snyder_1959_351.9531178.5356Snyder, G. L. Little SitkinLittle Sitkin dacite from coast at stream mouth 0.8 mile south of terminus of crater flow of West Cove memberAndesite of Little Sitkin dacite. Color: medium gray (N 5). Texture: hypocrystalline, porphyritic with feldspar phenocrysts as much as 4 mm in diameter, and pyroxene phenocrysts as much as 3 mm long. Plagioclase megaphenocrysts, 20-30 percent, range from An35 to An56 and average An47; complex zoning and twinning common. Clinopyroxene, 8 percent, contains rare centers of orthopyroxene, 1 percent. Both unreacted olivine, 5 percent, and pyroxene are stained amber along joints. Magnetite, 2 percent, as anhedrons. Average composition of feldspar microlites in trachytic groundmass is An42.Snyder_1959_3Whole Rock 55.47 0.89 17.76 8.21 0.17 4.04 8.79 3.29 1 0.17 100.09424NN3.045.45H2OM=0.07; H2OP=0.15; CO2=0NN 18.6 366 8.2 745XRFB V=0.001, M=SPEC, R=424;Ba V=0.03, M=SPEC, R=424;Sr V=0.07, M=SPEC, R=424;K V=0.83, M=NN, R=745;Yb V=0.0002, M=SPEC, R=424;Y V=0.002, M=SPEC, R=424;Zr V=0.008, M=SPEC, R=424;Ni V=0.001, M=SPEC, R=424;Co V=0.003, M=SPEC, R=424;Cr V=0.002, M=SPEC, R=424;Cu V=0.006, M=SPEC, R=424;V V=0.03, M=SPEC, R=424;Ga V=0.001, M=SPEC, R=424;Sc V=0.002, M=SPEC, R=424;Mo V=0.0002, M=SPEC, R=424;

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