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SAMPLE INFO : Snyder_1959_6
Sample ID:Snyder_1959_6
Station ID:Snyder_1959_6
Latitude:51.9531
Longitude:178.5356
Datum:NAD83
Sample Type 1:Lava
Field Lithology:Dacite
 Text Description:
Low-silica dacite of Little Sitkin dacite. Color: medium gray (N 5). Texture: hypocrystalline, massive. Plagioclase, 20 to 25 percent, ranges in composition from An55 to An72; a few have fritted centers. Orthopyroxene, 2-3 percent, and clinopyroxene, 2-3 percent, both distinctly pleochroic in light pink and light green; a few orthopyroxene and clinopyroxene centers in differently oriented clinopyroxene crystals. One relict olivine grain, with a thick reaction rim of pyroxene and magnetite. No oxyhornblende xenocrysts although this mineral is plentiful in nearby thin laminae of rhyodacite. Groundmass brownish glass filled with magnetite dust and crystallites.

References:
Geology of Little Sitkin Island, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDSample Type 1Sample Type 2Final UnitMaterialSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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_651.9531178.5356Snyder, G. L. Little SitkinLittle Sitkin dacite from interfingered contact zone on north side of rhyodacite of Pratt Point member about 0.9 mile south of East PointLow-silica dacite of Little Sitkin dacite. Color: medium gray (N 5). Texture: hypocrystalline, massive. Plagioclase, 20 to 25 percent, ranges in composition from An55 to An72; a few have fritted centers. Orthopyroxene, 2-3 percent, and clinopyroxene, 2-3 percent, both distinctly pleochroic in light pink and light green; a few orthopyroxene and clinopyroxene centers in differently oriented clinopyroxene crystals. One relict olivine grain, with a thick reaction rim of pyroxene and magnetite. No oxyhornblende xenocrysts although this mineral is plentiful in nearby thin laminae of rhyodacite. Groundmass brownish glass filled with magnetite dust and crystallites.Snyder_1959_6LavaWhole-rock 58.92 0.75 17.12 6.8 0.15 3.21 7.19 3.39 1.34 0.15 99.81424NN2.64.5H2OM=0.23; H2OP=0.71; CO2=0.01NN 26.8 318 7.4 units are percent 1.1745XRF: Rb, Sr, Ni; NN: K;

SAMPLE LOCATION

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