A Brief Note On Volcanoes

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Volcanoes - Research
1) Find a cross section of a volcano that is clear and easy to understand and paste it below.

2) Describe the following products of a volcano and explain how they can be dangerous to humans:
a) Ash cloud- The ash cloud is composed of rock, minerals and volcanic glass. It is formed during eruptions. It can disrupt planes and to inhale the ash is dangerous.
b) Volcanic bombs- Is a mass of molten rock that is larger than 65mm in width. It can be thrown over large distances and is extremely hot. It is ejected as liquid or plastic but then solidifies or changes form.
c) Lava flow- a mass of flowing or solidified lava. Lava flows are the least hazardous of all processes in volcanic eruption. How far a lava flow travels depends on the flows temperature, silica content, extrusion rate, and slope of the land. Lava flows do not move very fast so people rarely get killed by them. They are very hot (between 550-1400 degrees) so people can get burnt.
d) Pyroclastic flow- Are fluidized masses of rock fragments and gases that move rapidly in response to gravity. Pyroclastic flows can move very fast. Small pyroclastic flows can move as fast as 10 to 30 m/s while larger flows can move at rates of 200 m/s. If you are near pyroclastic flow you will most certainly die.
3) Define the following terms, find a photograph of and determine the location of each type of volcano:
a) Dormant- is an active volcano that is not erupting, but supposed to erupt again. Mt Etna- Catania, Italy

b) Extinct-An extinct volcano has not had an eruption for at least 10,000 years and is not expected to erupt again in a comparable time scale of the future.
c) Shield volcano- a broad domed volcano with gently sloping sides, characteristic of the eruption of fluid, basaltic lava.
d) Stratovolcano- a volcano built up of alternate layers of lava and ash.
e) Lava dome- a mound of viscous lava which has been extruded from a volcanic vent.

4) Explain why humans continue to live at the base of a volcano:
Humans
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