Submarine landslides around the Canary Islands.

Krastel, Sebastian, Schmincke, Hans-Ulrich , Jacobs, Colin L., Rihm, Roland, Le Bas, Timothy P. and Alibes, Barbara (2001) Submarine landslides around the Canary Islands. Open Access Journal of Geophysical Research: Solid Earth, 106 (B3). pp. 3977-3997. DOI 10.1029/2000JB900413.

[img]
Preview
Text
jgrb12645.pdf - Published Version

Download (2332Kb) | Preview

Supplementary data:

Abstract

The morphology and structure of the submarine flanks of the Canary Islands were mapped using the GLORIA long-range side-scan sonar system, bathymetric multibeam systems, and sediment echosounders. Twelve young (<2 Ma) giant landslides have been identified on the submarine flanks of the Canary Islands up to now. Older landslide events are long buried under a thick sediment cover due to high sedimentation rates around the Canary Islands. Most slides were found on the flanks of the youngest and most active islands of La Palma, El Hierro, and Tenerife, but young giant landslides were also identified on the flanks of the older (15–20 Ma) but still active eastern islands. Large-scale mass wasting is an important process during all periods of major magmatic activity. The long-lived volcanic constructive history of the islands of the Canary Archipelago is balanced by a correspondingly long history of destruction, resulting in a higher landslide frequency for the Canary Islands compared to the Hawaiian Islands, where giant landslides only occur late in the period of active shield growth. The lower stability of the flanks of the Canaries is probably due to the much steeper slopes of the islands, a result of the abundance of highly evolved intrusive and extrusive rocks. Another reason for the enhanced slope instability is the abundance of pyroclastic deposits on Canary Islands resulting from frequent explosive eruptions due to the elevated volatile contents in the highly alkalic magmas. Dike-induced rifting is most likely the main trigger mechanism for destabilization of the flanks. Flank collapses are a major geological hazard for the Canary Islands due to the sector collapses themselves as well as triggering of tsunamis. In at least one case, a giant lateral blast occurred when an active magmatic or hydrothermal system became unroofed during flank collapse.

Document Type: Article
Keywords: Submarine landslides, Canary Islands, RV Charles Darwin, CD109, RV Meteor, M43/1
Research affiliation: OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-MUHS
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1029/2000JB900413
ISSN: 0148-0227
Projects: GLORIA Kanaren
Expeditions/Models/Experiments:
Date Deposited: 03 Apr 2017 08:25
Last Modified: 08 Apr 2019 13:13
URI: http://oceanrep.geomar.de/id/eprint/37351

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...