A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that
allows hot lava ... Erupting volcanoes can pose many hazards, not only in the
immediate vicinity of the eruption. ...
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
Oct 25, 2010 ... Mount Merapi is expected to erupt at any moment, and Indonesian officials ... "
Rising magma causes solid rock to break, sending earthquake ...
Volcanic activity frequently occurs at the boundaries of the Earth's tectonic plates
... An eruption can be preceded by hundreds of small earthquakes know as ...
Nov 30, 2010 ... It's time for our weekly Just Ask feature, where the experts tackle your questions
on science and technology. John Eichelberger, a volcano ...
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.
Eruptions can cause lateral blasts, lava flows, hot ash flows, mudslides,
avalanches, falling ash and floods. Volcano eruptions have been known to knock
A secondary school revision resource for GCSE Geography covering key facts
about volcanoes and volcanic eruptions.
How many volcanoes erupt every day? ... How does a volcano build up the
pressure to erupt? The magma ... How can you tell if a volcanic eruption might