Dataset Information

Seismic control of large prehistoric rockslides in the Eastern Alps.

ABSTRACT: Large prehistoric rockslides tend to occur within spatio-temporal clusters suggesting a common trigger such as earthquake shaking or enhanced wet periods. Yet, trigger assessment remains equivocal due to the lack of conclusive observational evidence. Here, we use high-resolution lacustrine paleoseismology to evaluate the relation between past seismicity and a spatio-temporal cluster of large prehistoric rockslides in the Eastern Alps. Temporal and spatial coincidence of paleoseismic evidence with multiple rockslides at ~4.1 and ~3.0 ka BP reveals that severe earthquakes (local magnitude M_L 5.5-6.5; epicentral intensity I₀ VIII¼-X¾) have triggered these rockslides. A series of preceding severe earthquakes is likely to have progressively weakened these rock slopes towards critical state. These findings elucidate the role of seismicity in preparing and triggering large prehistoric rockslides in the European Alps, where rockslides and earthquakes typically occur in clusters. Such integration of multiple datasets in other formerly glaciated regions with low to moderate seismicity will improve our understanding of catastrophic rockslide drivers.

SUBMITTER: Oswald P

PROVIDER: S-EPMC7886888 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Seismic control of large prehistoric rockslides in the Eastern Alps.

Oswald Patrick P Strasser Michael M Hammerl Christa C Moernaut Jasper J

Nature communications 20210216 1

Large prehistoric rockslides tend to occur within spatio-temporal clusters suggesting a common trigger such as earthquake shaking or enhanced wet periods. Yet, trigger assessment remains equivocal due to the lack of conclusive observational evidence. Here, we use high-resolution lacustrine paleoseismology to evaluate the relation between past seismicity and a spatio-temporal cluster of large prehistoric rockslides in the Eastern Alps. Temporal and spatial coincidence of paleoseismic evidence wit ...[more]

PMID: 33594074

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Dataset Information

Seismic control of large prehistoric rockslides in the Eastern Alps.

Publications

Seismic control of large prehistoric rockslides in the Eastern Alps.

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