Size-Frequency Relationship of Submarine Landslides at Convergent Plate Margins: Implications for Hazard and Risk Assessment

Behrmann, Jan H., Völker, David, Geersen, Jacob, Harders, Rieka and Weinrebe, Wilhelm (2014) Size-Frequency Relationship of Submarine Landslides at Convergent Plate Margins: Implications for Hazard and Risk Assessment Submarine Mass Movements and Their Consequences: 6th International Symposium. Advances in Natural and Technological Hazards Research, 37 . Springer International Publishing, Cham, pp. 165-175. ISBN 978-3-319-00971-1 DOI 10.1007/978-3-319-00972-8_15.

[img] Text
scan_2017-03-22_11-52-03r.1.pdf - Reprinted Version
Restricted to Registered users only

Download (907Kb)

Supplementary data:

Abstract

We use complete inventories of submarine landslides from the Middle America (MA) and the Central Chile (CC) trench and forearc systems to analyze the size-frequency relationship of such structures on active continental slopes. The MA forearc is characterized by subduction erosion, and the CC forearc has had an accretionary tectonic history since the Late Neogene. Both are end-member types of convergent margins around the world. Both margin segments have been mapped by high-resolution swath bathymetry at strike lengths of about 1,300 km (MA) and 1,000 km (CC). The Middle America forearc has 143 discernible slides with sizes ranging from 0.38 to 1,426 km2. Offshore Central Chile, the 62 mapped slides are 0.9–1,285 km2 in size. Slide localization is markedly different at both margin types. While they also vary strongly along strike of the individual margin, depending on forearc slope gradient, kinematic coupling between plates, or topographic structure of the downgoing plate, the size-frequency relationships are remarkably similar. This allows quantification of the incidence of a submarine slide of given size per margin segment. The relationships hold for slide sizes from 10 to 1,000 km2, with the cut-off defined by slide size (smaller slides) and sample size (larger slides). As slide traces of 100–300 km2 size are obliterated by tectonic deformation after about 200,000 years, recurrence rates for slides of a given size can be estimated. This offers a chance to assess hazard and risk resulting from such events. It is suggested that it takes 20 to 200 plate boundary earthquakes to set off a medium-sized (>10 km2) or larger slump or slide.

Document Type: Book chapter
Additional Information: Das Buch ist in der GEOMAR-Bibliothek vorhanden!
Keywords: Convergent plate boundary, Tectonics, Erosion, Accretion, Submarine landslide, Chile, Central America
Research affiliation: OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Marine Geodynamics
DOI etc.: 10.1007/978-3-319-00972-8_15
Date Deposited: 10 Dec 2013 11:24
Last Modified: 22 Mar 2017 12:08
URI: http://eprints.uni-kiel.de/id/eprint/22507

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...