Volcanos Flashcards
How is the volcano formed?
- A volcano is a mountain formed by the eruption of magma on the Earth surface through a whole vent and the Earth‘s crossed example Mount Fuji in Japan
- Once it reaches the surface, the magma is called lava
- Lava cools quickly to form basalt rock
- How explosive a volcano depends on the amount of silica there is in the magma.
- Magma with a lot of silica traps lots of gas within it. Making it sticky and thick like honey. this causes a violent interruption.
- Layers of ash, dust, and lava make the cone grow bigger
- If the magma contains less silica, less gases, trapped, making it more like water so when it erupt, it is less explosive making a wider shield shaped volcano cone
- Sometimes the force of an eruption is so strong that it can blast the mountain to pieces
- A mix of dust, gas and rocks are called. Pyroclasts
What does active mean?
Active means the volcano has erupted in recent times (past 100 years) example Mount Saint Helens 1980
What does dormant mean?
has not corrupted in over 100 years, but may erupt again example Mount Fuji Japan
What does extinct mean?
Has not erupted in historic times, example Mount Slemish Co. Antrim
Positive effects of volcanic activity
Tourism - Pompeii was destroyed by Mount of Vesuvius erupting in 70 9AD. Tourists now visit the excavated city, which is good for the local economy. ( economic factor)
Fertile soil - volcanic ash makes surrounding soil fertile, which is good for farming. E.g fruit farms surrounding Mount Vesuvius (Italy) (environmental, economic factor)
Geological energy - is green energy created by volcanic rock in Iceland 90% of homes are heated by geothermal energy and most industry runs due to it (environmental ,)
Negative impacts of volcanic Activity.
Loss of life - Pompeii 79 A.D. 20,000 people lost their lives due to Mount Vesuvius eruption (social)
Destruction of property - Hawaii 2023 people lost their homes due to volcanic eruptions (social)
Damage and destroy crops - ash can damage and destroy crops. This can lead to famine, crops worldwide dying causing famine. Environmental, economic)
About the Mount Saint Helen eruption
- Mount Saint Helens is located in south western Washington about 50 miles north west of Portland.
- mount Saint Helens last corrupted on May 18, 1980
- mount Saint Helens was a lateral eruption
- Loss of death was a big impact of Mt St Helens killing 57 people due to the eruption (social impact)
- Destruction of property was another impact of Mt St Helens about 200 times or destroyed. This was a social impact.
- Damage and destruction of crops this led to famine this is an environmental impact.
