Sample: 94SJP12

Sample ID:	94SJP12 ^[1]
Station ID:	94SJP12
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:	Approximately 20’ thick dike trending N33°E that cuts through the brecciated unit (sBA9) at Site 12. Fine grained, vesicular, holocrystalline, seriate to glomeroporphyritic with a matrix of opaque, plagioclase, orthopyroxene, microlites, zircon? and minor alteration. Plagioclase phenocrysts (An26 - An62) are up to 2.3 mm and commonly are oscillatory zoned, some grains have sieve textured cores, and rounded rims or resorption embayments. Orthopyroxene phenocrysts are up to 0.75 mm and are strongly pleochroic with some opaque inclusions. Amphibole phenocrysts are up to 1.0 mm, display green-yellow pleochroism with rims dehydrated to small opaques; some opaque amphibole pseudomorphs. Opaque phenocrysts are up to 0.2 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5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex: Miami University (Ohio) unpublished Ph.D. dissertation, 547 p.

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