English: Alaska's Aleutian Volcanic Arc consists of dozens of volcanoes, all formed by subduction of the Pacific Plate beneath the North American Plate. This volcanic ash sample is from Mt. Redoubt, a ~900,000 year old andesitic-dacitic-basaltic stratovolcano. Redoubt had an explosive ash eruption in April 2009. The tephra is composed of pulverized porphyritic andesite. This sample is from a distal airfall ash deposit.

Locality of source volcano: Mt. Redoubt, far-northeastern Aleutian Range, western side of the Cook Inlet, Lake Clark National Park, Kenai B-8 1:63,360 USGS topographic quadrangle, ~105 miles southwest of the city of Anchorage, southern Alaska, USA (60° 29’ 07" North latitude, 152° 44' 39" West longitude)

Provenance: collected at the town of Anchor Point, Alaska (~92 kilometers south-southeast of Mt. Redoubt)

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See info. at: en.wikipedia.org/wiki/Mount_Redoubt and

en.wikipedia.org/wiki/2009_Mount_Redoubt_eruptive_activity