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SAMPLE INFO : 8
Sample ID:8
Station ID:8
Latitude:57.18
Longitude:-170.3
Datum:NAD83
Date Sampled:1948-01-01
Sample Type 1:Lava
Sample Type 2:Flow
Text Description:
Sample of a dense flow of chrystophyric hyalobasanite, cropping out over a distance of several miles along the west shore (and under Einahnuhto Bluffs) of St. Paul Island. The rock is gray with finely crystalline groundmass studded with clear, yellow phenocrysts of olivine from 1 mm to 10 mm across, some zoned; refractive index and 2V angle correspond to about Fa20. Very few phenocrysts are clinopyroxene; they are always zoned and usually pitted and intergrown with minerals of the groundmass. Refractive index and 2V angle correspond to He40. The glassy groundmass includes small grains of olivine and pyroxene. Small plagioclase laths form a mesh; indices of refraction lie in the range 1.555-1.565, indicating about An55. The glass shows incipient crystallization, index, n=1.53-1.54.

References:
Geology and petrology of the Pribilof Islands, 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
857.18-170.3Barth, T. F. W.1948-01-01 St. Paul IslandWest shore of St. Paul IslandSample of a dense flow of chrystophyric hyalobasanite, cropping out over a distance of several miles along the west shore (and under Einahnuhto Bluffs) of St. Paul Island. The rock is gray with finely crystalline groundmass studded with clear, yellow phenocrysts of olivine from 1 mm to 10 mm across, some zoned; refractive index and 2V angle correspond to about Fa20. Very few phenocrysts are clinopyroxene; they are always zoned and usually pitted and intergrown with minerals of the groundmass. Refractive index and 2V angle correspond to He40. The glassy groundmass includes small grains of olivine and pyroxene. Small plagioclase laths form a mesh; indices of refraction lie in the range 1.555-1.565, indicating about An55. The glass shows incipient crystallization, index, n=1.53-1.54.8Whole Rock 44.41 2.19 12.75 11.36 0.18 14.72 9.3 3 1.41 0.71 100.14301NN2.159.42H2OM=0.05; H2OP=0.2NN

SAMPLE LOCATION

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