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83 Pico de Teide, Tenerife Island, Canary Archipelago Pico de Teide (16°38′W, 28°18′N) is a 3,718 m high volcano in the Tenerife Island, Canary volcanic archipelago, off the northwestern coast of Africa in the Atlantic Ocean. The Tenerife’s original huge caldera Las Cañadas was formed during the Late Tertiary and Early Quaternary by empting volcano’s large magmatic hearth in combination with the following collapse of the mountain summit. Large caldera of the volcano is of 12–20 km in diameter; it is partly filled by the present cones of Montana Blanca, Pico Viejo, an explosive crater, and the highest point of Pico de Teide. The main volcanic stage culminated about five million years ago. The birth of the Canary islands’ volcanoes and of the whole archipelago can be explained by a hot-spot theory, based on the prospect of magmatic reservoirs of melted lava in the Earth’s mantle. According to this prospect, one of these hot spots is located deep below the region in question; hot masses melted and weakened the upper-lying rock strata and subsequently enabled the passage of the melt to the sur- face. The concept of the hot-spot occurrence under Canaries fits well the tectonic structure and the structural disturbances in the northwest part of the African plate. In addition to Pico de Teide, there are several other active volcanoes in this region. The island Lanzarote (670 m a.s.l.) was formed as a volcano some 20 million years ago, and is typical by its linear lava outflows. Basalt lava during the eruption in 1730–1736 (near Montanas del Fuego) and in 1824 (Nuevo del Fuego) covered about one quarter of the island. Also, volcanic activities in the Palma Island (2,426 m) should be mentioned; in 1585, almost 1,000-m high stromboli-type cone Tahuya was created (composed of papilla, mixture of cinder, and volcanic bombs); 60 years later (in 1645), another cone, San Martin, appeared there. Three illustrations invite us to the Atlantic coast of Africa, namely the Tenerife island dominated by a beautiful cone of Pico de Teide, climbing high above sea level, however, towering to approximately 7,500 m above the floor of the Atlantic Ocean. Pico de Teide is the highest mountain of Spain and the highest point in the Atlantic Ocean. The island of Tenerife itself is the world’s third largest volcanic island by its volume. Figure 63 (top) confirms the dominant position of the vol- cano on the island. Since the Spanish colonization in 1402, the volcano has been active several times. Reportedly, Cristobel Colón (Christopher Columbus) was a witness of one of its eruptions. Two centuries later, in 1704, a strong earthquake struck the island and the eruption from Pico’s central crater caused havoc in coastal town Garachico, in which numerous victims were reported. The next eruption, this time from the side craters, followed in 1798. The last lava outflow in 1909 at the northwest slope fortunately did not cause any considerable damage. Figure 63 (bottom) provides the possibility to view one of the Pico’s craters as it looked in 1835, when the volca- nic activity was weak; that time, the crater was only about 30 m deep and 400 m in diameter. The escaping steam and vol- canic gases did not prevent the access of the observers. In con- trast to the relatively small size of the inner crater, the whole caldera was ∼ 55 km in circumference. Figure 64 enables us to assess the topography of the volcano. We have to keep in mind that in 1835, the volcano had two major craters, namely Pico de Teide and Pico Viejo, which together can be considered as a double stratovolcano. According to the image, there were three localities, where lava tore up the caldera rim and made its way down toward the fertile coastal lands and further to the sea. A number of smaller-size creaters and vents opened and fed their own lava fields. J. Kozák and V. Čermák, The Illustrated History of Natural Disasters, © Springer Science+Business Media B.V. 2010
