Sample: 94SJP52B

Sample ID:	94SJP52B ^[1]
Station ID:	94SJP52B
AT Num:
Volcano:	Skookum Creek
Possible source:
Eruption:
Collector:	Preece, S. J.
Date sampled:	1994-00-00
Sample type 1:	Lava
Color:
Final unit:
Text Description:	A 40-60’ thick vitrophyre that contains contorted flow folds at Site 5. Fine grained, holocrystalline, porphyritic with a matrix of cryptocrystalline material, feldspar and opaque. Plagioclase phenocrysts (An27 - An42) are up to 3.25 mm and most have normal zoning; some have oscillatory zoning. Orthopyroxene phenocrysts are up to 1.1 mm and some have opaque inclusions and/or amphibole rims. Amphibole phenocrysts are up to 1.75 mm with green-yellow pleochroism, and some have opaque inclusions; one grain is rimmed with orthopyroxene. Opaque phenocrysts are up to 0.5 mm. 80.9% matrix, 13.0% plagioclase, 1.0% orthopyroxene, 0.4% opaque, 2.0% amphibole, 2.7% vesicles.
Sample Location:

References Cited

[1] Geochemical variation in the less than 5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex, 1997

Preece, S. J., 1997, Geochemical variation in the less than 5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex: Miami University (Ohio) unpublished Ph.D. dissertation, 547 p.

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