Sample: 93SJP67

Sample ID:	93SJP67 ^[1]
Station ID:	93SJP67
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:	Blocks of vitrophyre in scree from Dome F at Site 4. Fine grained, holocrystalline, porphyritic with a matrix of cryptocrystalline material, feldspar, quartz?, opaque and alteration. Plagioclase phenocrysts (An34 - An38) are up to 4.0 mm and most are rounded; there is often strong oscillatory zoning. Opaque phenocrysts are up to 0.4 mm. There is an altered phase that is now an opaque rim with a core of unidentifiable high relief crystals ± plagioclase. A second altered phase, larger in size, consists of serpentine/chlorite and calcite.
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5 Ma Wrangell Volcanic Field, Alaska, with an emphasis on the Skookum Creek volcanic complex: Miami University (Ohio) unpublished Ph.D. dissertation, 547 p.

This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G22AC00137 and G23AC00070.

Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.