Sample: 94SJP77

Sample ID:	94SJP77 ^[1]
Station ID:	94SJP77
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:	At least 30’ thick, wall-like, blocky outcrop at South Pass. Fine grained, holocrystalline, porphyritic with a matrix of cryptocrystalline material, opaque, plagioclase and alteration. Plagioclase phenocrysts are up to 1.75 mm and occasionally have strong normal zoning, resorption embayments and/or alteration. Orthopyroxene phenocrysts are up to 1.2 mm and some have opaque inclusions. Clinopyroxene phenocrysts are up to 0.65 mm. Opaque phenocrysts are up to 0.5 mm. Trachydacite.
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5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex: Miami University (Ohio) unpublished Ph.D. dissertation, 547 p.

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