Sample: 93SJP45

Sample ID:	93SJP45 ^[1]
Station ID:	93SJP45
AT Num:
Volcano:	Skookum Creek
Possible source:
Eruption:
Collector:	Preece, S. J.
Date sampled:	1993-00-00
Sample type 1:	Lava
Color:
Final unit:
Text Description:	Outcrop of black vitrophyre, ~4-5’ below the epiclastic unit at Site 1 in the Boyden Hills. Sample is from float below the outcrop. Fine grained, hypocrystalline, pilotaxitic, porphyritic to glomeroporphyritic with a matrix of glass, plagioclase, opaque, apatite, zircon, and microlites. Plagioclase phenocrysts (An32 - An35) are up to 3.12 mm and larger grains occasionally have normal zoning. Opaque phenocrysts are up to 0.6 mm,, but most are matrix size. Orthopyroxene phenocrysts are up to 1.1 mm with intense pleochroism and occasionally have opaque inclusions. Biotite? or amphibole? phenocrysts are up to 0.08 mm.
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5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex: Miami University (Ohio) unpublished Ph.D. dissertation, 547 p.

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