how does a volcano start?
what is; a weak spot on earth where lava comes out.
where does magma come from?
what is; under the ground.
what is a fault?
what is; a break is the earth's crust where two sides have moved.
what is an earthquake?
what is; a sudden and violent shaking of the earth's surface, caused by a sudden release of energy from the earth's lithosphere, that creates seismic waves.
what is a "p-wave"?
what is; a wave from an earthquake that goes by fast, and results in little to no damage.
what does magma consist of?
what is; melted rock.
what are "s-waves"?
what is; a fast moving wave, faster than a p-wave but slower than surface-wave, and produces medium damage, more damage than a p-wave yet less than a surface-wave.
what are seismic waves?
what is; an elastic wave produced by an earthquake, and sometimes also by a volcano.
what is an extinct volcano?
what is; a "dead volcano" that will never erupt again.
what is intensity?
what is; the amount of damage done by an earthquake.
where does the energy from an earthquake come from?
where is; from plate tectonics.
what is a seismograph?
what is; am instrument that records seismic waves from an earthquake.
what is a focus?
what is; a the point inside the earth where an earthquake begins.
what are surface waves?
what are; the slowest, most intense waves, take a long time to pass and create major damage.
what is an epicenter?
what is; the point on the earth's surface directly above the focus.
what is a composite volcano?
what is; a combination of tall cones and lower hills that make up a volcanic region.
what is a sheild volcano?
what is; a wide, low mountain with quiet eruptions.
where are most volcanoes found?
what is; the ring of fire.
where do earthquakes occur?
what is; along transform plate boundaries.
what is a magma chamber?
what is; magma in a large pocket under a volcano.
what is a caldera?
what is; a huge hole left from a volcano after it has collapsed.
how are earthquakes measured?
what is; by using a moment magnitude scale (most common)
what is a dormant volcano?
what is; a "sleeping volcano" has a chance of "waking up", or erupting in the future.
what is an island arc?
what is; a chain of active volcanoes found where two plates touch.
what is a cone volcano?
what is; a tall spherical hill or mountain (now a volcano)