Alaska Volcano Observatory

Not a visible tephra layer: cryptotephra. 396–401 cm depth in core. Glass shards are colourless, pumiceous to highly vesicular and bubble-wall shaped. Their median is about 50 microns, the maximum shard size being 90 microns. Few greenish and rare brownish shards and one single feldspar crystal with a glass rim also occur

Sample Location:

Great Sitkin

Spurr

+−

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Legend

	Red (Warning)
	Orange (Watch)
	Yellow (Advisory)
	Green (Normal)
	Uninstrumented
	Geologic Sites

50 km

50 mi

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References Cited

[1] Linking the North Atlantic to central Europe: A high-resolution Holocene tephrochronological record from northern Germany, 2002

van den Bogaard, C., and Schmincke, H.U., 2002, Linking the North Atlantic to central Europe: A high-resolution Holocene tephrochronological record from northern Germany: Journal of Quaternary Science, v. 17, p. 3-20, doi: 10.1002/jqs.636

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