Sample: 81-ARh-19


Sample ID: 81-ARh-19 [1]
Station ID: 81-ARh-19
AT Num:
Volcano:
Possible source:
Eruption:
Collector: Richter, D. H.
Date sampled: 1981-00-00
Sample type 1: Lava
Color:
Final unit:
Text Description: Wrangell Lava. Dacite flow-dome and plug. Pale-red to light-gray massive flow dome exhibiting a columnar-jointed base and a crackled and brecciated, medium-gray glassy plug (?) (shown by crosses). Rock is porphyritic containing phenocrysts of plagioclase (12-15%, as large as 3 mm), oxyhornblende (2-3%, 2 mm), hypersthene (trace to 1%, 2 mm) and traces of opaque minerals in a cryptocrystalline matrix.
Sample Location:

References Cited

[1] Geologic map of the Nabesna B-6 Quadrangle, south-central Alaska, 1993

Richter, D. H., Smith, J. G., Schmoll, H. R., and Smith, R. L., 1993, Geologic map of the Nabesna B-6 Quadrangle, south-central Alaska: U.S. Geological Survey Geological Quadrangle Map GQ 1688, unpaged, 1 sheet, scale 1:63,360.