Sample: 81-ARh-33


Sample ID: 81-ARh-33 [1]
Station ID: 81-ARh-33
AT Num:
Volcano: Tanada Peak
Possible source:
Eruption:
Collector: Richter, D. H.
Date sampled: 1981-00-00
Sample type 1: Lava
Color:
Final unit:
Text Description: Wrangell Lava. Tanada volcano. Shield lavas. Chiefly dark-gray to medium-gray, thin to medium (2-10 m) flows of sparsely porphyritic andesite and basaltic andesite and minor intercalated laharic and pyroclastic deposits. Flows contain phenocrysts of plagioclase (1-2%, 1-5 mm), augite (0-1%, 1-2 mm), and traces of hypersthene, olivine, and opaque minerals in a microfelty to pilotaxitic groundmass. * * * In the adjacent Nabesna B-5 quadrangle (Lowe and others, 1982) the andesite and basaltic andesite flows of their unit QTaf are mostly equivalent to Tanada shield lavas.
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.