2006-11-27 08:53:59 · 6 answers · asked by brittany g 1 in Science & Mathematics ➔ Earth Sciences & Geology
In a phrase, volcanic rock.
Each volcano erupts constructively and destructively, and some of those constructive eruptions build the sides of the volcano. The type of magma determines the color and shape.
2006-11-27 08:55:30 · answer #1 · answered by QFL 24-7 6 · 0⤊ 0⤋
It depends on the type of volcano, but they are generally formed of the following things ejected from the volcano itself: lava (either liquid or cooled in the air), ash, and pieces of rock.
"Shield" volcanoes (broad, gently sloping cones like Hawaii) are mostly composed of built up lava flows of basalt. These can be huge.
"Cinder cones" are sometimes very small volcanoes, sometimes on the flanks of other volcanoes, made of pyroclasts (solidified magma which formed rock fragments of different textures and sizes).
"Composite" volcanoes or "stratovolcanoes" are pretty much alternating layers of lava and pyroclasts, like Mt. Vesuvius.
"Calderas" are huge collapsed volcanic craters that form after a violent eruption when the empty magma chamber caves in. Yellowstone is for a large part a caldera. Pyroclastic flows and other volcanic debris can be found around the crater.
2006-11-27 09:01:42 · answer #2 · answered by Patchy O'Squirrel 2 · 0⤊ 0⤋
Rocks
Or a Indian Taco covered in burnt hair
2006-11-27 09:02:26 · answer #3 · answered by sooners83 4 · 0⤊ 0⤋
molten rock lava magma.pressure from below forces lava to erupt.
2006-11-27 09:03:06 · answer #4 · answered by Anonymous · 0⤊ 0⤋
they are formed by underground pressure of molten rock called Magma...when they erupt, they land, cool, and form the shape...the flowing molten rock is called lava....
2006-11-27 08:57:42 · answer #5 · answered by Anonymous · 0⤊ 1⤋
molten rock and lava
2006-11-27 08:58:40 · answer #6 · answered by roobeng.indahouse 3 · 0⤊ 0⤋