Repeated debris avalanches on Tenerife and genesis of Las Canadas caldera wall (Canary Islands)

Geologic evidence on Tenerife, Canary Islands, indicates six successive nor th-directed debris avalanche events, including: the Anaga and Teno (ca. 6 M a) events that affected the old basaltic series, and the Tigaiga (>2.3 Ma). Roques de Garcia (possibly 0.6-0.7 Ma). Orotava (ca. 0.6 Ma), and Icod (<0 .15 Ma) avalanche events that affected the Canadas and Dorsal volcanic edif ices. The approximate total volume (>1000 km(3)) inferred for these events can account for the volume of previous estimates of offshore volcanic debri s, These repeated flank failures can also account for the present morpholog y of Las Canadas caldera wall, which partly bounds a multiepisodic lateral- collapse structure 25 km wide.