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SAMPLE INFO : 2
Sample ID:2
Station ID:2
Latitude:51.9531
Longitude:178.5356
Datum:NAD83
Sample Type 1:Lava
Field Lithology:Andesite
Text Description:
Andesite from typical inclusion in lavas of Double Point dacite. Color: dark gray (N 3). Texture: miarolitic intersertal. Pore space, miarolitic cavities: 20-30 percent. Plagioclase lathes, 45-55 percent, average An60 but range from An26 to An74; megaphenocrysts, 3 percent, show fritted texture. Oxyhornblende, 14 percent, is pleochroic in deep brown and olive brown, occurs in needles with a length-width ratio of 15:1; many hornblende crystals have hollow centers. Orthopyroxene, 6 percent, occurs in euhedral needles with a length-width ratio as much as 30:1. Clinopyroxene, 4 percent, is present as stubby subhedral crystals. Magnetite, 4 percent, anhedrons have a length-width ratio as much as 10:1. Clear brown glass, 14 percent, in groundmass bas N=1.498.

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
251.9531178.5356Snyder, G. L. Little SitkinCollected from small inlier of Double Point dacite about 1 mile west-northwestward of summit of Little Sitkin volcanoAndesite from typical inclusion in lavas of Double Point dacite. Color: dark gray (N 3). Texture: miarolitic intersertal. Pore space, miarolitic cavities: 20-30 percent. Plagioclase lathes, 45-55 percent, average An60 but range from An26 to An74; megaphenocrysts, 3 percent, show fritted texture. Oxyhornblende, 14 percent, is pleochroic in deep brown and olive brown, occurs in needles with a length-width ratio of 15:1; many hornblende crystals have hollow centers. Orthopyroxene, 6 percent, occurs in euhedral needles with a length-width ratio as much as 30:1. Clinopyroxene, 4 percent, is present as stubby subhedral crystals. Magnetite, 4 percent, anhedrons have a length-width ratio as much as 10:1. Clear brown glass, 14 percent, in groundmass bas N=1.498.2Whole Rock 55.31 0.85 18.01 8.27 0.15 3.94 8.63 3.13 1.1 0.15 99.92424NN4.454.23H2OM=0.05; H2OP=0.41; CO2=0NN 17.4 457 7.7 745XRFK V=0.9, M=NN, R=745;

SAMPLE LOCATION

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