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Earth Science Quiz Answer to types of volcanoes


Geologists generally group volcanoes into four main kinds:
composite volcanoes, cinder cones, shield volcanoes, and lava domes.

Composite volcanoes
Some of the Earth's grandest mountains are composite volcanoes -- sometimes called stratovolcanoes. They'are typically steep-sided, symmetrical cones of large dimension built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs. These may rise as much as 8,000 feet above their bases.

Cinder cones
Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone. Most cinder cones have a bowl-shaped crater at the summit and rarely rise more than a thousand feet or so above their surroundings.

composite volcano
composite volcano
seild volcano
sheild volcano

Shield volcanoes
Shield volcanoes are built almost entirely of fluid lava flows. Flow after flow pours out in all directions from a central summit vent or group of vents. These build a broad, gently sloping cone of flat, domical shape, with a profile much like that of a warrior's shield. Some of the largest volcanoes in the world are shield volcanoes.

Lava domes
Volcanic or lava domes are formed by relatively small, bulbous masses of lava too viscous to flow any great distance: consequently, on extrusion, the lava proceeds to pile over and around its vent. A dome grows largely by expansion from within. As it grows, its outer surface cools and hardens. Then it shatters, spilling loose fragments down its sides. Volcanic domes commonly occur within the craters or on the flanks of large composite volcanoes.

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