Analyzing turbidity, suspended-sediment concentration, and particle-size distribution resulting from a debris flow on Mount Jefferson, Oregon, November 2006

Mark A. Uhrich

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USGS · 70156409

Analyzing turbidity, suspended-sediment concentration, and particle-size distribution resulting from a debris flow on Mount Jefferson, Oregon, November 2006

Mark A. Uhrich

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Abstract

A debris flow and sediment torrent occurred on the flanks of Mt Jefferson in Oregon on November 6, 2006, inundating 150 acres of forest. The massive debris flow was triggered by a rock and snow avalanche from the Milk Creek glaciers and snowfields during the early onset of an intense storm originating near the Hawaiian Islands. The debris flow consisted of a heavy conglomerate of large boulders, cobbles, and coarse-grained sediment that was deposited at depths of up to 15 ft and within 3 mi of the glaciers, and a viscous slurry that deposited finer-grained sediments at depths of 0.5 to 3 ft. The muddy slurry coated standing trees within the lower reaches of Milk Creek as it moved downslope.

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Source-reported bounding extent: 44.652245428089714° to 44.70919886592671° latitude; -121.84146239616743° to -121.76067463308715° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Mark A. Uhrich. 2010. Analyzing turbidity, suspended-sediment concentration, and particle-size distribution resulting from a debris flow on Mount Jefferson, Oregon, November 2006. https://pubs.usgs.gov/publication/70156409

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