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SAMPLE INFO : 84-ARh-98
Sample ID:84-ARh-98
Station ID:84-ARh-98
Latitude:62.225
Longitude:-144.237
Datum:NAD83
Date Sampled:1984-00-00
Sample Type 1:Other
Sample Type 2:Plutonic
Field Lithology:Rhyolite
Sample Unit:Qsr
Text Description:
Mount Sanford hypabyssal rhyolite pluton (Pleistocene). Small, massive, reddish-gray, porphyritic hornblende rhyolite associated with west Sanford eruptive center. Rock contains phenocrysts of plagioclase (5-8%, average 1 mm) and hornblende (trace to 1%, average <1 mm; locally altered), in trachyitic groundmass of plagioclase and hornblende microlites in cryptocrystalline matrix. Pluton may be ring-fracture intrusion along postulated caldera wall.

References:
Geologic map of the Gulkana A-1 Quadrangle, south-central 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
84-ARh-9862.225-144.237Richter, D. H.1984-00-00SanfordMount Sanford rocks within Gulkana A-1 quadrangle. Latitude and longitude derived from paper map.Mount Sanford hypabyssal rhyolite pluton (Pleistocene). Small, massive, reddish-gray, porphyritic hornblende rhyolite associated with west Sanford eruptive center. Rock contains phenocrysts of plagioclase (5-8%, average 1 mm) and hornblende (trace to 1%, average <1 mm; locally altered), in trachyitic groundmass of plagioclase and hornblende microlites in cryptocrystalline matrix. Pluton may be ring-fracture intrusion along postulated caldera wall.84-ARh-98Whole Rock 70.3 0.22 16 1.9 0.09 0.73 2.64 4.85 1.83 0.15 99.492262NN1.830.25H2OP=0.93; H2OM=0.24; CO2=0.01RAPIDA

SAMPLE LOCATION

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