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SAMPLE INFO : 74ALe-56
Sample ID:74ALe-56
Station ID:74ALe-56
Latitude:62.1204
Longitude:-144.7501
Datum:NAD83
Date Sampled:1974-00-00
Sample Type 1:Lava
Sample Type 2:Flow
Field Lithology:Dacite
Text Description:
Thick lobate flows of dacite and minor rhyodacite that form massive piles along west, northwest, north, and northeast flanks of Mount Drum, apparently erupted from central vent. Rocks are light to pinkish medium gray, weather dark reddish brown, and are porphyritic with phenocrysts (1-3 mm) of plagioclase, hypersthene, hornblende, and rare to minor biotite and augite in a pilotaxitic to trachyitic groundmass. Probably related in age to late hornblende-biotite dacite domes (Qldd).

References:
Geologic map of the Gulkana A-2 quadrangle, Alaska

GEOCHEM DATA