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USGS · 70014515

Catastrophic flooding and eruption of ash-flow tuff at Medicine Lake volcano, California

J.M. Donnelly-Nolan·K.M. Nolan
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Abstract

Catastrophic flooding has eroded a discontinuous network of oversized anastomosing channels on the northwest flank of the Medicine Lake volcano. Most of these previously unrecognized channels were cut into an andesitic ash-flow tuff; boulders as large as 2 m in intermediate diameter were moved in terrain where little rain falls today and stream erosion is nonexistent or minimal. The flooding was probably triggered by eruption of andesite tuff through a late Pleistocene ice cap on the volcano, about 60,000 to 70,000 or about 130,000 B.P.

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J.M. Donnelly-Nolan, K.M. Nolan. 1986. Catastrophic flooding and eruption of ash-flow tuff at Medicine Lake volcano, California. https://doi.org/10.1130/0091-7613(1986)14%3C875%3Acfaeoa%3E2.0.co%3B2

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