Volcanic Misconceptions State whether
each statement is true or false. If
false correct the statement to make it true.
1.All igneous rocks are of volcanic origin.
2.Earthquakes associated with volcanoes are from tectonic movement.
3.All intrusive igneous rocks are exposed because of weathering/erosion.
4.Granite is a common rock in the Hawaiian islands.
5.One would expect to find piles of pumice in and around mafic volcanic sites.
6.Lava kills the most people during volcanic eruptions.
7.Lahars only happen when it rains after an eruption.
8.Composite cones (stratovolcanoes) have layers that are strongly bonded.
9.Shield volcanoes are explosive and the lateral blasts can be devastating.
10.Felsic eruptions often begin with a ‘warning blast’ out the top.
11.Alaska is home to many shield volcanoes.
12.Dante’s Peak was a classic example of mafic volcano.
13.Basalt is less dense than granite.
14.The Aleutian Islands are a classic example of a ‘hot spot.’
15.Alaska has a couple of volcanoes, no more than any other state.
16.After Dante’s Peak erupted one would expect to find basalt all over the place.
17.Redoubt and Mt. Spur were formed from a mafic magma body.
18.The pH of the water will drop to a point that it melts boats (but not fish) during
an eruption.
19.The more Silica in a magma body, the more gas that is held in.
20.All volcanic gasses are highly poisonous.