A volcano begins as melted rock (magma) which rises from deep inside the earth
toward the surface. As the gas-filled magma rises ...
Volcanoes erupt because of density and pressure. The lower density of the
magma relative to the surrounding rocks causes it to rise (like air bubbles in
When a part of the earth's upper mantle or lower crust melts, magma forms. A
volcano is essentially an opening or a vent through which this magma and the ...
Volcanoes erupt due to pressure that the weight of the rocks puts on the magma
and forces it to the surface out any available vent or exit provided to it.
Oct 25, 2010 ... Mount Merapi is expected to erupt at any moment, and Indonesian officials ... "
Rising magma causes solid rock to break, sending earthquake ...
We currently know of 80 or more which are under the oceans. ... volcano What
causes volcanoes to erupt? The Earth's crust is made up of huge slabs called ...
... forces molten matter to be expelled out to the surface, causing a volcanic
eruption. ... Did you know? ... The mantle is made up of molten material and
Eruptions can cause lateral blasts, lava flows, hot ash flows, mudslides,
avalanches, falling ash and floods. Volcano eruptions have been known to knock
Jan 6, 2016 ... What causes the world's explosive volcanic eruptions, like the 1980s ... gas
bubbles form from the magma in a process known as vesiculation, ...
Jan 5, 2015 ... The eruption of a volcano can be one of the planet's most destructive events —
spewing huge amounts ... How It Happens | Man-Made Quakes.