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SAMPLE INFO : 94SJP11A
Sample ID:94SJP11A
Station ID:94SJP11A
Latitude:62.28850246
Longitude:-143.267
Datum:NAD83
Date Sampled:1994-00-00
Sample Type 1:Lava
Sample Type 2:Dike
Text Description:
A vertical dike trending S65°E that intruded into the brecciated unit (sBA9) at Site 12. There is a 10 cm chill margin that is very glassy. Fine grained, vesicular, hypocrystalline, seriate porphyritic with a matrix of plagioclase, opaque, pale brown glass, microlites and orthopyroxene?. Plagioclase phenocrysts (An39 - An52) are up to 1.7 mm and both normal and oscillatory zoning are common; the largest grains often have thin overgrowth rims. Amphibole phenocrysts are up to 0.8 mm, and dehydrated to granular opaque masses with green-brown pleochroic cores; most grains are entirely replaced. Orthopyroxene phenocrysts are up to 0.25 mm. Opaque phenocrysts are up to 0.5 mm (primary not pseudomorphs after amphibole). 83.7% matrix, 10.1% plagioclase, 0.3% opaque, 0.1% altered phase, 0.1% alteration, 5.7% vesicles. Trachydacite.

References:
Geochemical variation in the less than 5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex

GEOCHEM DATA
StationIDLatitudeLongitudeGeologistDateVisitedAge InfoVolcanoEruptionLocation DescriptionText DescriptionSample IDSample Type 1Sample Type 2Final UnitMaterialSiO2TiO2Al2O3FeOTMnOMgOCaONa2OK2OP2O5Total-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
94SJP11A62.28850246-143.267Preece, S. J.1994-00-00 Skookum CreekNabesna B-5; T6N, R12E, S19A vertical dike trending S65°E that intruded into the brecciated unit (sBA9) at Site 12. There is a 10 cm chill margin that is very glassy. Fine grained, vesicular, hypocrystalline, seriate porphyritic with a matrix of plagioclase, opaque, pale brown glass, microlites and orthopyroxene?. Plagioclase phenocrysts (An39 - An52) are up to 1.7 mm and both normal and oscillatory zoning are common; the largest grains often have thin overgrowth rims. Amphibole phenocrysts are up to 0.8 mm, and dehydrated to granular opaque masses with green-brown pleochroic cores; most grains are entirely replaced. Orthopyroxene phenocrysts are up to 0.25 mm. Opaque phenocrysts are up to 0.5 mm (primary not pseudomorphs after amphibole). 83.7% matrix, 10.1% plagioclase, 0.3% opaque, 0.1% altered phase, 0.1% alteration, 5.7% vesicles. Trachydacite.94SJP11ALavaWhole-rock 64.94 0.62 16.89 4.17 0.21 1.08 2.96 6.01 1.86 0.31 99.2755DCP4.584.17LOI=0.93DCP 19.8 594 433 46 458 17.8 5.6 0.8 6 2bdl 2 3 103 19.5 55XRF: Rb, Zr, Nb, Th, U, Ni, Ga; DCP: Ba, Sc, V; MX: Sr, Y, Cu, Zn;

SAMPLE LOCATION

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