Multiple Caldera Collapses Inferred From The Shallow Electrical Resistivity Signature Of The Las Canadas Caldera, Tenerife, Canary Islands

Jump to: navigation, search


OpenEI Reference LibraryAdd to library

Journal Article: Multiple Caldera Collapses Inferred From The Shallow Electrical Resistivity Signature Of The Las Canadas Caldera, Tenerife, Canary Islands

Abstract
The Las Canadas caldera of Tenerife (LCC) is a well exposed caldera depression filled with pyroclastic deposits and lava flows from the active Teide-Pico Viejo complex (TPVC). The caldera's origin is controversial as both the formation by huge lateral flank collapse(s) and multiple vertical collapses have been proposed. Although vertical collapses may have facilitated lateral slope failures and thus jointly contribute to the exposed morphology, their joint contribution has not been clearly demonstrated. Using results from 185 audiomagnetotelluric (AMT) soundings carried out between 2004 and 2006 inside the LCC, our study provides consistent geophysical constraints in favour of multiple vertical caldera collapse. One-dimensional modelling reveals a conductive layer at shallow depth (30-1000 m), presumably resulting from hydrothermal alteration and weathering, underlying the infilling resistive top layer. We present the resistivity distribution of both layers (resistivity images), the topography of the conductive layer across the LCC, as well as a cross-section in order to highlight the caldera's evolution, including the distribution of earlier volcanic edifices. The AMT phase anisotropy reveals the structural and radial characteristics of the LCC.

Authors 
Nicolas Coppo, Pierre-Andre Schnegg, Wiebke Heise, Pierik Falco and Roberto Costa








Published Journal 
Journal of Volcanology and Geothermal Research, 2008





DOI 
Not Provided
Check for DOI availability: http://crossref.org



 

Citation

Nicolas Coppo,Pierre-Andre Schnegg,Wiebke Heise,Pierik Falco,Roberto Costa. 2008. Multiple Caldera Collapses Inferred From The Shallow Electrical Resistivity Signature Of The Las Canadas Caldera, Tenerife, Canary Islands. Journal of Volcanology and Geothermal Research. (!) .