These landslide sketches by Annette Patton, a landslide expert from University of Oregon, depict how the 11.2-Mile slide capitalized on loose soil deposits on the mountain's bedrock steps to gain both size and speed. During their August site visit, the experts noted seeing surviving blueberry bushes on the edge of one step, proving that the slide cascaded so quickly down the bedrock that the soil quite literally flew over the blueberry bushes, leaving them untouched.
WRANGELL - Unique bedrock formations, a thick layer of loose sediment, and a concentrated water drainage system flowing down from the ridgetop were three of the main ingredients that led to the Nov. 20, 2023, landslide that killed six people at 11.2-Mile.
These three causes, all benign on their own, became disastrous when heavy rains down poured on Wrangell Island. Though the airport weather station reported rainfall conducive to a "large but not especially large" storm, members of the public who live close to the landslide location told the team of experts that their personal rainfall data ta...
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