Brdo sa kraterom (otvorom) na vrhu kroz koje, iz užaernih dubina Zemlje, izbijaju usijani komadi ruda, plinova i pepela; tj. usijana vulkanska lava koja se razliva i sve uništava oko sebe.
Mesto na Zemlji gde je ona toliko duboko otvorena da iz njene vrele unutrašnjosti mogu izbijati na površinu tople pare i gasovi, vruć pepeo, usijano kamenje i rastopljene stene; vatreni breg (naziv po bogu Vulkanu).
ETYM Italian volcano, vulcano, from Latin Vulcanus Vulkan, the god of fire. Related to Vulkan.
A mountain formed by volcanic material.
Crack in the Earth’s crust through which hot magma (molten rock) and gases well up. The magma is termed lava when it reaches the surface. A volcanic mountain, usually cone shaped with a crater on top, is formed around the opening, or vent, by the buildup of solidified lava and ashes (rock fragments). Most volcanoes arise on plate margins (see plate tectonics), where the movements of plates generate magma or allow it to rise from the mantle beneath. However, a number are found far from plate-margin activity, on “hot spots” where the Earth’s crust is thin.
There are two main types of volcano.
Composite volcanoes, such as Stromboli and Vesuvius in Italy, are found at destructive plate margins (areas where plates are being pushed together), usually in association with island arcs and coastal mountain chains. The magma is mostly derived from plate material and is rich in silica. This makes a very stiff lava such as andesite, which solidifies rapidly to form a high, steep-sided volcanic mountain. The magma often clogs the volcanic vent, causing violent eruptions as the blockage is blasted free, as in the eruption of Mount St Helens, Washington state, in 1980. The crater may collapse to form a caldera.
Shield volcanoes, such as Mauna Loa in Hawaii, are found along the rift valleys and ocean ridges of constructive plate margins (areas where plates are moving apart), and also over hot spots. The magma is derived from the Earth’s mantle and is quite free-flowing. The lava formed from this magma— usually basalt—flows for some distance over the surface before it sets and so forms broad low volcanoes. The lava of a shield volcano is not ejected violently but simply flows over the crater rim.
The type of volcanic activity is also governed by the age of the volcano. The first stages of an eruption are usually vigorous as the magma forces its way to the surface. As the pressure drops and the vents become established, the main phase of activity begins, composite volcanoes giving pyroclastic debris and shield volcanoes giving lava flows. When the pressure from below ceases, due to exhaustion of the magma chamber, activity wanes and is confined to the emission of gases and in time this also ceases. The volcano then enters a period of quiescence, after which activity may resume after a period of days, years, or even thousands of years. Only when the root zones of a volcano have been exposed by erosion can a volcano be said to be truly extinct.
Many volcanoes are submarine and occur along mid-ocean ridges.
The chief terrestrial volcanic regions are around the Pacific rim (Cape Horn to Alaska); the central Andes of Chile (with the world's highest volcano, Guallatiri, 6,060 m/19,900 ft); North Island, New Zealand; Hawaii; Japan; and Antarctica. There are more than 1,300 potentially active volcanoes on Earth. Volcanism has helped shape other members of the Solar System, including the Moon, Mars, Venus, and Jupiter's moon Io.
Staroitalski bog ognja (naročito njegove razorne snage) i metalskih radnika ili kovača, sa radionicom u vulkanu Etni; sin Jupitera i Junone, muž Venerin (odgovara grčkom Hefajstu).
In Roman mythology, the god of fire and destruction, later identified with the Greek god Hephaestus.
(Roman mythology) God of fire and metal working; counterpart of Greek Hephaestus.