Geological and geomechanical models of the pre-landslide volcanic edifice of Güímar and La Orotava mega-landslides (Tenerife)

摘要: Abstract The geological and geomechanical characterizations of the volcanic rock mass succession affected by Guimar La Orotava mega-landslides (Tenerife, Canary Island) are presented here for first time. estimated subaerial volume rocks mobilized each these landslides is in range 30–50 km3, one largest known world. Field data, gallery surveys borehole drilling have allowed main types materials their structural arrangement to be identified. Based on information a model pre-landslide edifice proposed. A palaeo-morphological reconstruction has been produced possible slope angles heights presented. Five lithological units identified emerged part edifice, three them forming flanks two axis island. On flanks, lava flows predominate with different degrees alteration proportion dikes increasing near axis. predominant pyroclastic deposits, dikes. In submarine four distinguished, formed hyaloclastites, pillow-lavas, gravitational deposits (slope basin facies). characterization obtained from field boreholes, laboratory tests literature review. models provide fundamental basis explanation instability processes that generated mega-landslides.