WHAT ARE VOLCANOES?
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WHAT ARE VOLCANOES?
Their description, where they are to be found and their formation. Description of magma, craters, chimney and volcanic cones. The Kailua Volcano. Fissure and Central Volcanoes. Other types of volcanoes: Hawaiian, Strombolian, Vulcanian and Pelean volcanoes. The explosion of the Island of Krakatoa. Volcanic zones. Summary.
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INTRODUCTION
- Ancient civilisations were afraid of volcanoes and respected them. Some thought that volcanoes were gods.
- Modification of the landscape
- How are volcanoes formed?
- Magma frequently ascends in the oceans.
- In other areas, subterranean pockets are formed and produce volcanic eruptions
DESCRIPTION OF VOLCANOES
- What are volcanoes? The magma.
- Structure of the volcanoes. Volcanic seat, chimney and crater.
- Cones. The Fujiyama.
- The eruption of a volcano
- Lava. The Etna Volcano.
- The Kailua Volcano.
TYPES OF VOLCANOES
- Fissure volcanoes and central volcanoes.
- During the Tertiary Era, fissure volcanoes belched wave after wave of basalt during millions of years and covered enormous areas.
- Central volcanoes: Hawaiian, Strombolian, Vulcanian
- Characteristics of the different central volcanoes: Stromboli, Etna, Kailua, Vesuvius
- The explosion at the Krakatoa island had a force equivalent to 3,000 times that of the Atomic Bomb which was dropped on Hiroshima and was heard from a distance of some 5,000 kilometres.
VOLCANIC ZONES
- There are approximately 500 active volcanoes on our planet.
- Around two-thirds of them are to be found within the so-called “Ring of Fire” in the Pacific.
- The spectacular eruption of a Mexican volcano as it was observed from a satellite.
- Another chain of volcanoes is situated in the middle of the Atlantic Ocean, and is formed mainly of submerged volcanoes, except in the case of Iceland.
- A third concentration of volcanoes is found in the Rift Valley System of Africa, where such volcanoes as Mounts Kilimanjaro or Kenya are located
- Another important group is found in the Mediterranean and include the legendary Vesuvius, Stromboli and Etna Volcanoes.
SUMMARY |
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