Sample: 79AMm 34


Sample ID: 79AMm 34 [1]
Station ID: 79AMm 34
AT Num:
Volcano: Gas Rocks, the
Possible source:
Eruption:
Collector: Miller, T. P.
Date sampled: 1979-01-01
Sample type 1: Other
Color: light gray
Final unit:
Text Description: Hypabyssal plug of light-gray (N7) dacite porphyry. Phenocryst phases are hornblende, biotite, plagioclase (An 48), and quartz. Phenocrysts are dominated by plagioclase, and less abundant hornblende and biotite in a glassy groundmass. Quartz is in blebs although it appears primary. Plagioclase phenocrysts have overgrowths over corroded cores. Rock is partly vesicular.
Sample Location:

References Cited

[1] Map and tables showing geochronology and whole-rock geochemistry of selected samples, Ugashik and part of Karluk quadrangles, Alaska, 1992

Wilson, F.H., and Shew, Nora, 1992, Map and tables showing geochronology and whole-rock geochemistry of selected samples, Ugashik and part of Karluk quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1539-E, 34 p., 2 sheets, scale 1:250,000.