UNITA DIDATTICA SUI VULCANI Prof Daniele Baldissin Che

UNITA’ DIDATTICA SUI VULCANI (Prof. Daniele Baldissin)

Che cos’è un vulcano?

Proprietà chimico-fisiche del magma

Proprietà chimico-fisiche del magma

Pahoehoe lava (Kilauea) Termine hawaiano: “dove si può camminare a piedi nudi”. La lava solidifica in superficie mentre al di sotto continua a scorrere

Stratovulcano

Vulcano a scudo

Tipi di eruzione

Sulla superficie terrestre si trovano vulcani ovunque il materiale proveniente dal mantello riesce ad arrivare in superficie: • Dorsali medio oceaniche • Hot spot (punti caldi) • Zone di subduzione

Fasi esplosive dell’Etna

Pinatubo - Filippine The 1991 eruption of Pinatubo volcano in the Philippines created a new caldera with an average diameter of 2. 5 km. Caldera collapse, which lowered the height of the volcano about 300 m, occurred following the ejection of nearly 10 cu km of tephra in one of the world's largest eruptions of the 20 th century. This 1994 view from the NW shows a lake filling the caldera floor and two small islands from a partially submerged lava dome that was erupted in 1992.

Pinatubo – Filippine (Fumarole)

Fuji - Giappone Winter snows cover the slopes of Mount Fuji, Japan's highest and most renowned volcano. A 700 m-wide crater caps the 3776 -m-high stratovolcano. The modern symmetrical cone is constructed over a group of overlapping volcanoes, a remnant of which, Hoei-san, forms the knob halfway down the SE (left) flank. The diagonal line at the lower right is a toll road that extends to timberline on the north flank. Historical eruptions have been recorded since the 8 th century, the latest in 1707.

Darwin - Galapagos

Etna - Italia Stratovulcano – Vulcano più alto d’Europa (Altezza: 3350 m)

Barcena - Messico

Tolbachik - Kamchatka

Vulcani in Giappone, Taiwan

Hawaii e pacifico

Europa e Mediterraneo