000029666 001__ 29666
000029666 005__ 20130225122325.0
000029666 0248_ $$aoai:doc.rero.ch:20120828091613-DM$$ppostprint$$prero_explore$$zthesis_urn$$zpreprint$$zreport$$zthesis$$zbook$$zjournal$$zcdu16$$zcdu556$$zcdu1$$zdissertation$$zunine$$zcdu34
000029666 041__ $$aeng
000029666 080__ $$a556
000029666 100__ $$aCoppo, Nicolas$$uGeomagnetism Group, Institute of Geology and Hydrogeology, University of Neuchâtel, Switzerland
000029666 245__ $$9eng$$aConductive structures around Las Cañadas caldera, Tenerife (Canary Islands, Spain): A structural control
000029666 520__ $$9eng$$aExternal eastern areas of the Las Cañadas caldera (LCC) of Tenerife (Canary Islands, Spain) have been investigated using the audiomagnetotelluric (AMT) method with the aim to characterize the physical rock properties at shallow depth and the thickness of a first resistive layer. Using the results of 50 AMT tensors carried out in the period range of 0.001 s to 0.3 s, this study provides six unpublished AMT profiles distributed in the upper Orotava valley and data from the Pedro Gil caldera (Dorsal Ridge). Showing obvious 1-D behaviour, soundings have been processed through 1-D modeling and gathered to form profiles. Underlying a resistive cover (150-2000 Ωm), a conductive layer at shallow depth (18-140 Ωm, 250-1100 m b.g.l.) which is characterized by a “wavy-like” structure, often parallel to the topography, appears in all profiles. This paper points out the ubiquitous existence in Tenerife of such a conductive layer, which is the consequence of two different processes: a) according to geological data, the enhanced conductivity of the flanks is interpreted as a plastic breccia within a clayish matrix generated during huge lateral collapse; and b) along main tectonic structures and inside calderas, this layer is formed by hydrothermal alteration processes. In both areas, the conductive layer is thought to be related to major structural volcanic events (flank or caldera collapse) and can be seen as a temporal marker of the island evolution. Moreover, its slope suggests possible headwall locations of the giant landslides that affected the flanks of Tenerife.
000029666 695__ $$9eng$$aMagnetotelluric method ; Caldera ; Hydrothermal alteration ; Lateral collapse ; Tenerife
000029666 700__ $$aSchnegg, Pierre-André$$uGeomagnetism Group, Institute of Geology and Hydrogeology, University of Neuchâtel, Switzerland
000029666 700__ $$aFalco, Pierik$$uGeomagnetism Group, Institute of Geology and Hydrogeology, University of Neuchâtel, Switzerland
000029666 700__ $$aCosta, Roberto$$uGeomagnetism Group, Institute of Geology and Hydrogeology, University of Neuchâtel, Switzerland
000029666 773__ $$g2010/8/1/67-82$$tGeologica Acta
000029666 775__ $$gPublished Version$$ohttp://dx.doi.org/10.1344/105.000001516
000029666 8564_ $$fCoppo_Nicolas-Conductive_structures_around_Las_Canadas-20120828.pdf$$qapplication/pdf$$s2907893$$uhttp://doc.rero.ch/record/29666/files/Coppo_Nicolas-Conductive_structures_around_Las_Canadas-20120828.pdf$$yorder:1$$zTexte intégral
000029666 918__ $$aFaculté des sciences$$bRue Emile-Argand 11, 2007 Neuchâtel
000029666 919__ $$aUniversité de Neuchâtel$$bNeuchâtel$$ddoc.support@rero.ch
000029666 980__ $$aPOSTPRINT$$bUNINE$$fART_JOURNAL
000029666 990__ $$a20120828091613-DM