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SAMPLE INFO : 9
Sample ID:9
Station ID:9
Latitude:51.9531
Longitude:178.5356
Datum:NAD83
Sample Type 1:Lava
Field Lithology:Dacite
Text Description:
Low-silica dacite of the Patterson Point formation. Color: light brownish gray (5 YR 6/1). Texture: hypocrystalline, vesicular with "hairy" pumice developed locally, porphyritic with pyroxene and feldspar phenocrysts as much as 3 mm long. Plagioclase, 25-30 percent, varies from An43 to An70 and has an average composition of An51; subgraphic areas of brownish glass and two-fluid negative crystals are included within the plagioclase. Clinopyroxene, 5 percent, and orthopyroxene, 4 percent, in part form agglomerations with magnetite-ilmenite, 1 percent. Groundmass consists of clear pink to brown glass (N=1.506) containing many small gas bubbles.

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
951.9531178.5356Snyder, G. L. Little SitkinPatterson Point formation, from stream cut 0.9 mile north of the summit of the 1,980-foot mountain.Low-silica dacite of the Patterson Point formation. Color: light brownish gray (5 YR 6/1). Texture: hypocrystalline, vesicular with "hairy" pumice developed locally, porphyritic with pyroxene and feldspar phenocrysts as much as 3 mm long. Plagioclase, 25-30 percent, varies from An43 to An70 and has an average composition of An51; subgraphic areas of brownish glass and two-fluid negative crystals are included within the plagioclase. Clinopyroxene, 5 percent, and orthopyroxene, 4 percent, in part form agglomerations with magnetite-ilmenite, 1 percent. Groundmass consists of clear pink to brown glass (N=1.506) containing many small gas bubbles.9Whole Rock 60.67 0.72 17.02 5.7 0.13 2.7 6.11 3.74 1.43 0.16 99.74424NN2.533.42H2OM=0.17; H2OP=1.39; CO2=0.01NN 29.3 263 8.2 745XRFK V=1.18, M=NN, R=745;

SAMPLE LOCATION

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Page modified: July 14, 2014 13:37
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