Tsunami Deposits Related to Flank Collapse in Oceanic Volcanoes: The Agaete Valley Evidence, Gran Canaria, Canary Islands

Autor: Juan Carlos Carracedo, María del Carmen Cabrera, Patrick Wassmer, Francisco-Jose Perez-Torrado, Raphaël Paris, Francisco Guerra Santana, Jean-Luc Schneider, Ángel Rodríguez-Santana
Přispěvatelé: Laboratoire de Géographie Physique et Environnementale (GEOLAB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Laboratorio de Dinamica de Populaçoes manihas (DIMAR), Universidade Federal de Pernambuco [Recife] (UFPE), Comisión Interministerial de Ciencia y Tecnología, CICYT (España), Gobierno de Canarias, Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Clermont Auvergne (UCA)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2006
Předmět:
Zdroj: Marine Geology
Marine Geology, 2006, 227 (1-2), pp.135--149. ⟨10.1016/j.margeo.2005.11.008⟩
Digital.CSIC. Repositorio Institucional del CSIC
instname
DOI: 10.1016/j.margeo.2005.11.008⟩
Popis: 15 pages, 9 figures.-- Printed version published Mar 15, 2006.
Enigmatic marine conglomerates are attached at 41–188 m asl to the walls of the valley of Agaete, on the northwest coast of Gran Canaria (Canary Islands). They are formed by heterogeneous, angular to rounded heterometric volcanic clasts (roundness and maximal size decreasing with altitude), and fossils (rhodolites and marine shells), never found in growth position and often broken. The deposits are internally stratified into several layers, most of them showing very poor sorting, matrix-supported and reverse grading. They present lenticular morphologies with poor lateral continuity in transversal and longitudinal sections. Slopes show values and orientations similar to those of the relief of the substratum to which they seem to adapt. Although they show clear evidence of erosive contact with the substratum (rip up clasts), they do not tend to form horizontal terraces. Soft materials (soils and colluviums) are preserved in the contact with the substratum in outcrops with deposit slopes of up to 15°. The age of the deposits is constrained between 1.75 Ma and 32 ka. Their altitude and slope distributions are not related to Pleistocene interglacial sea level changes, storm deposits or isostatic movements. All the above suggests that the Agaete marine deposits were generated by tsunami waves, the most probable source being a flank failure, at least nine major such events having occurred in the Canary Islands during the Pleistocene. The Güímar sector collapse (east coast of Tenerife,< 0.83 Ma, > 30 km3) is the closest possible source for the tsunami and the sole flank failure that is directed towards another island in the Canaries.
This work is a part of CICYT (PB96-0243) and Canary Island Government (PI2002/148) projects, as well as a Picasso (French–Spanish research collaboration) HF2001-0037 project.
Databáze: OpenAIRE
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