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SAMPLE INFO : 79AWs 17
Sample ID:79AWs 17
Station ID:79AWs 17
Latitude:57.259268850194
Longitude:-156.82540177362
Datum:NAD83
Date Sampled:1979-01-01
Sample Type 1:Lava
Field Lithology:Dacite
Text Description:
Medium-light gray (N 6), porphyritic dacite (S; high-silica andesite G). Major phases are clinopyroxene, orthopyroxene (hypersthene), plagioclase (An 58 and possibly An 40), and glass. Phenocrysts of plagioclase and pyroxene as much as 7 mm in length in a very fine grained to aphanitic groundmass of plagioclase, glass, and opaque minerals. In thin section, areas of the groundmass are more transparent than others; these more transparent areas contain fewer opaque minerals and are located in areas of augite concentration. Sample contains two types of plagioclase phenocrysts; some are poikilitic and have overgrown edges, and others are unaltered, free of inclusions, and may have resorbed edges. Most plagioclase phenocrysts of both types have compositions between An 60 to 70, although some may have compositions nearer to An 40.

References:
Map and tables showing geochronology and whole-rock geochemistry of selected samples, Ugashik and part of Karluk quadrangles, Alaska

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedVolcanoLocation DescriptionText DescriptionSample IDSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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
79AWs 17 57.259268850194 -156.82540177362 Wilson, F. H. 1979-01-01 KialagvikUgashik B-3, northwest of Kialagvik near VABM GobMedium-light gray (N 6), porphyritic dacite (S; high-silica andesite G). Major phases are clinopyroxene, orthopyroxene (hypersthene), plagioclase (An 58 and possibly An 40), and glass. Phenocrysts of plagioclase and pyroxene as much as 7 mm in length in a very fine grained to aphanitic groundmass of plagioclase, glass, and opaque minerals. In thin section, areas of the groundmass are more transparent than others; these more transparent areas contain fewer opaque minerals and are located in areas of augite concentration. Sample contains two types of plagioclase phenocrysts; some are poikilitic and have overgrown edges, and others are unaltered, free of inclusions, and may have resorbed edges. Most plagioclase phenocrysts of both types have compositions between An 60 to 70, although some may have compositions nearer to An 40.79AWs 17 61.362898764149 0.68958306428767 16.989727670856 5.8069510012856 0.12992144689478 3.0481570233006 6.5460421320061 2.9981872360333 1.79891234162 0.15990331925511 100.334092XRF2.693.39CO2=0.12; H2OP=0.21; H2OM=0.14XRF

SAMPLE LOCATION

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