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Landslides triggered by the 2002 Denali fault, Alaska, earthquake and the inferred nature of the strong shaking

R.W. Jibson·E. L. Harp·W. Schulz·D. K. Keefer
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Abstract

The 2002 M7.9 Denali fault, Alaska, earthquake triggered thousands of landslides, primarily rock falls and rock slides, that ranged in volume from rock falls of a few cubic meters to rock avalanches having volumes as great as 15 ?? 106 m3. The pattern of landsliding was unusual; the number of slides was less than expected for an earthquake of this magnitude, and the landslides were concentrated in a narrow zone 30-km wide that straddled the fault rupture over its entire 300-km length. The large rock avalanches all clustered along the western third of the rupture zone where acceleration levels and ground-shaking frequencies are thought to have been the highest. Inferences about near-field strong shaking characteristics drawn from the interpretation of the landslide distribution are consistent with results of recent inversion modeling that indicate high-frequency energy generation was greatest in the western part of the fault rupture zone and decreased markedly to the east. ?? 2004, Earthquake Engineering Research Institute.

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R.W. Jibson, E. L. Harp, W. Schulz, D. K. Keefer. 2004-08-01. Landslides triggered by the 2002 Denali fault, Alaska, earthquake and the inferred nature of the strong shaking. https://doi.org/10.1193/1.1778173

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