Rift zone reorganization through flank instability in ocean island volcanoes: an example from Tenerife, Canary Islands.

Walter, Thomas R., Troll, Valentin R., Cailleau, Béatrice, Belousov, Alexander, Schmincke, Hans-Ulrich , van den Bogaard, Paul and Amelung, F. (2005) Rift zone reorganization through flank instability in ocean island volcanoes: an example from Tenerife, Canary Islands. Bulletin of Volcanology, 67 (4). pp. 281-291. DOI 10.1007/s00445-004-0352-z.

[thumbnail of Walter.pdf] Text
Walter.pdf - Reprinted Version
Restricted to Registered users only

Download (1MB)

Supplementary data:

Abstract

The relationship between rift zones and flank instability in ocean island volcanoes is often inferred but rarely documented. Our field data, aerial image analysis, and 40Ar/39Ar chronology from Anaga basaltic shield volcano on Tenerife, Canary Islands, support a rift zone—flank instability relationship. A single rift zone dominated the early stage of the Anaga edifice (~6–4.5 Ma). Destabilization of the northern sector led to partial seaward collapse at about ~4.5 Ma, resulting in a giant landslide. The remnant highly fractured northern flank is part of the destabilized sector. A curved rift zone developed within and around this unstable sector between 4.5 and 3.5 Ma. Induced by the dilatation of the curved rift, a further rift-arm developed to the south, generating a three-armed rift system. This evolutionary sequence is supported by elastic dislocation models that illustrate how a curved rift zone accelerates flank instability on one side of a rift, and facilitates dike intrusions on the opposite side. Our study demonstrates a feedback relationship between flank instability and intrusive development, a scenario probably common in ocean island volcanoes. We therefore propose that ocean island rift zones represent geologically unsteady structures that migrate and reorganize in response to volcano flank instability.

Document Type: Article
Keywords: Tenerife, Rift zone, Dike intrusion, Volcano flank instability, Constructive-destructive feedback mechanism, Canary Islands
Research affiliation: OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-MUHS
Refereed: Yes
Open Access Journal?: No
Publisher: Springer
Date Deposited: 03 Dec 2008 16:51
Last Modified: 29 May 2018 07:45
URI: https://oceanrep.geomar.de/id/eprint/7753

Actions (login required)

View Item View Item