Earthquake Impact on Active Margins : Tracing Surficial Remobilization and Seismic Strengthening in a Slope Sedimentary Sequence
Strong earthquakes at active ocean margins can remobilize vast amounts of surficial slope sediments and dynamically strengthen the margin sequences. Current process understanding is obtained from resulting event deposits and low-resolution shear strength data, respectively. Here we directly target a...
| Veröffentlicht in: | Geophysical research letters. - 1984. - 46(2019), 11 vom: 16. Juni, Seite 6015-6023 |
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| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2019
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| Zugriff auf das übergeordnete Werk: | Geophysical research letters |
| Schlagworte: | Journal Article Japan Trench sediment transport seismic strengthening slope stability surficial remobilization |
| Zusammenfassung: | Strong earthquakes at active ocean margins can remobilize vast amounts of surficial slope sediments and dynamically strengthen the margin sequences. Current process understanding is obtained from resulting event deposits and low-resolution shear strength data, respectively. Here we directly target a site offshore Japan where both processes are expected to initiate, that is, at the uppermost part (15 cm) of a sedimentary slope sequence. Based on a novel application of short-lived radionuclide data, we identified, dated, and quantified centimeter-scale gaps related to surficial remobilization. Temporal correlation to the three largest regional earthquakes attest triggering by strong earthquakes (M w >8). Also, extremely elevated shear strength values suggest a strong influence of seismic strengthening on shallow sediments. We show that despite enhanced slope stability by seismic strengthening, earthquake-induced sediment transport can occur through surficial remobilization, which has large implications for the assessment of turbidite paleoseismology and carbon cycling at active margins |
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| Beschreibung: | Date Revised 13.10.2023 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 0094-8276 |
| DOI: | 10.1029/2019GL082350 |