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SAMPLE INFO : 46AC112
Sample ID:46AC112
Station ID:46AC112
Latitude:51.9242
Longitude:-177.1623
Datum:NAD83
Date Sampled:1946-01-01
Sample Type 1:Lava
Sample Type 2:Flow
Field Lithology:Andesite
Text Description:
Medium light-gray (N6) hypersthene andesite, conspicuously porphyritic and irregularly vesicular. Phenocrysts include plagioclase, augite, hypersthene, and hornblende. Plagioclase is labradorite with a median composition of An53, in crystals ranging in size from 0.1 to 2mm, commonly zoned, with the sequence of zones differing from one crystal to another. Salite, in dark-green crystals ranging in size from 0.1 to 0.5 mm, has nZ 1.712, suggesting a composition of Ca50Mg38Fe12. Hypersthene has nZ equal to 1.70, suggesting a composition of En72Fs28. Many of the hypersthene crystals have jackets of augite. The hornblende crystals are considerably resorbed, and are pleochroic from dark reddish-brown to yellow. The accessory minerals are magnetite or ilmenite, and psudodichroic apatite prisms. The groundmass consist of plagioclase crystals and augite needles in pale-brown glass whose index ranges from 1.50 to 1.495.

References:
Magmatic differentiation in Tertiary and Quaternary volcanic rocks from Adak and Kanaga Islands, Aleutian Islands, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedVolcanoEruptionLocation 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
46AC11251.9242-177.1623Unknown, Unknown1946-01-01KanagaLava flow, 8,400 feet sough 33.5 degrees east from the center of the crater of Kanaga volcano.Medium light-gray (N6) hypersthene andesite, conspicuously porphyritic and irregularly vesicular. Phenocrysts include plagioclase, augite, hypersthene, and hornblende. Plagioclase is labradorite with a median composition of An53, in crystals ranging in size from 0.1 to 2mm, commonly zoned, with the sequence of zones differing from one crystal to another. Salite, in dark-green crystals ranging in size from 0.1 to 0.5 mm, has nZ 1.712, suggesting a composition of Ca50Mg38Fe12. Hypersthene has nZ equal to 1.70, suggesting a composition of En72Fs28. Many of the hypersthene crystals have jackets of augite. The hornblende crystals are considerably resorbed, and are pleochroic from dark reddish-brown to yellow. The accessory minerals are magnetite or ilmenite, and psudodichroic apatite prisms. The groundmass consist of plagioclase crystals and augite needles in pale-brown glass whose index ranges from 1.50 to 1.495.46AC112Whole Rock 56.83 0.64 18.1 7.44 0.18 3.04 7.81 3.62 1.64 0.46 100.661085NN4.153.73H2OP=0.2; H2OM=0.08NN

SAMPLE LOCATION

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