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SAMPLE INFO : 3
Sample ID:3
Station ID: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
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 An42.3Whole 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

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