Volcanic Hazards

So, I thought I would give a little overview on the different hazards that derive from volcanoes.

Pyroclastic Flows: a fast moving current of hot gas and rock (also known as tephra) that move down the mountain at speeds of around 700 km/hr, and have been known to reach 1,000 C. Despite what happens in Dante's Peak, it is not possible to outrun a pyroclastic flow.

Ash Cloud: the mushroom like cloud that immediately forms when ash and tephra is released from the volcano. Depending on the wind patterns, the ash cloud will spread, making it appear that it is night time, when it may be noon.

Tephra: the material produced by the volcanic eruption. Tephra is usually rhyolitic, and the bigger the eruption, the more viscus the magma is.

Fires: an example of a fire caused by a volcano is when hot lava mixes with trees or brush, catching the igniting the wood.

Lahars: a lahar is a mudflow or landslide composed of pyroclastic material and water.

Lava: molten lava that is expelled from a volcano during an eruption. Lava can be classified on a scale of how viscous it is - how easily it flows.

Volcanic Gases: a gas given off by volcanoes, active or dormant, and they can be very poisonous.

Water Pollution: water pollution occurs when the volcanic ash, and the ash cloud mix with various bodies of water.

Landslides: an earthquake can start a volcano, but an earthquake can also start a landslide which helps trigger the volcano.

Disease: disease is a large part of volcanic eruptions for many reasons. One is that you can absorb large amounts of radiation. Also, if you breath in the volcanic ash, the moisture of your throat and interior body mix with the ash forming a cement like substance that suffocates you.

Tsunamis: an earthquake can start a tsunami when it has used all of it's erupt-able magma, and forms a crater from an empty magma chamber. That crater then fills with water, and if it happens quick enough, it creates a tsunami.