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GEOLOGI




La Palma is the north-westernmost island in the Canary Islands
(Spain), rising from the 4-km deep seafloor to a height of 2430 m above
sea level (Fig. 1). It has been volcanically active for at least 4 Ma. The
submarine basal complex started to form about 4 Ma ago (Staudigel and
Schmincke, 1984). Subaerial volcanism started about 1.8 Ma ago, with
the construction of different volcanic edifices in the northern half of the
island: Garafía (1.7–1.2 Ma), Taburiente-Cumbre Nueva (1.2–0.4 Ma)
and Bejenado (0.56–0.49 Ma). The Taburiente edifice has been affected
by huge landslides and intense erosion, exposing the submarine struc
ture at the bottom of the Taburiente caldera (Ancochea et al., 1994). The
volcanic activity migrated southward during the late stages of
Taburiente, culminating in Cumbre Nueva. This volcano suffered a giant
landslide on its western flank 560 ka ago (Carracedo et al., 2001). The
Bejenado volcano then arose through the landslide deposits, and after a
quiescent period, volcanic activity migrated southward about 123 ka
ago, building Cumbre Vieja. At Cumbre Vieja, the most active basaltic
volcanic field in the Canaries (Troll and Carracedo, 2016), vents are
mainly located in a 20 km north-south rift reaching up to 1950 m asl
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