What is a Volcano? You probably know; huge black hills that spew out tonnes and tonnes of pumice, ash and lava. One thing you might not know is some of the great eruptions: Mount Vesuvius, Krakatoa and the Yellowstone Supervolcano in the USA. You might wonder what causes a volcano to erupt. Well, they sit on places where the earth’s crust is particularly thin. The magma under it builds up pressure and eventually the magma escapes onto the surface, where it is known as lava. Over time, the lava cools and solidifies, making the volcano bigger.
There are different types of volcanoes. One is the Compound Volcano, which explodes violently when it erupts, throwing ash and rock far into the air. Another is the Cinder Cone Volcano, where the lava is thick and cools around the rim, forming a tall, steep mountain. Shield volcanoes have runnier lava, which trickles down the sides quickly. An underwater shield volcano created the islands of Hawaii.
On the cold, outer planets and moons of the solar system, there are even Cryovolcanoes, which erupt liquid methane instead of lava. The biggest volcano in the solar system is actually a shield volcano on Mars, which is over two times taller than Mount Everest. The dangers are still there though; tsunamis, piroclastic flows, toxic gas - even if there aren’t any people.
Yellowstone National Park, USA. 640K years ago.
This eruption was not like any other - in the rare occasion of a supervolcano erupting, such as this one, you will definitely need to evacuate; maybe even to another planet. The whole of America was trashed, covering the whole continent with lava and clearing all the visability from sight. But let’s not forget about the rest of the world - what happened to that? On the south side of things, South American and African farmers were dishearted to see all their crops burn to death, but probably didn’t expect their own deaths! Otherwise, the north wasn’t going easy either. The ash even reached Russia and Svalbard, Norway, but the only thing that hadn’t reached Russia was civilization!
Mount Vesuvius, Italy. 79 AD.
You’ve probably been taught this at school a few weeks ago, but here’s a recap. It happened on the 24th of August 79 AD, where it started off regular, but with a few normal tremors. When it had reached 10am, people started to notice animals fleeing and the ground shaking. At lunchtime, ash was really starting to pile up and the tiles and plastering were falling off at a rapid pace. Then by 2pm, oh my! Fires rose up to 3 metres and the properties were already reduced to rubble. But then at evening, it was too late for the people to flee, as the lava had killed them before.
Krakatoa, Indonesia. Late 1800s.
This was a volcano on an island. The eruption killed thousands of people nearby, but also caused huge landslides into the sea, creating massive tsunamis that swept across the sea, killing thousands more people. The eruption was so bigger, it could even be detected on the other side of the world.
Underwater Shield Volcano, in what is now Hawaii. 4.5 Million Years ago.
This seemingly ordinary underwater shield volcano in the Pacific ocean had never exploded, until, in one of the biggest eruptions yet, pushed up literally millions of tonnes of rock, ash and pumice up to the surface, where it drifted there for a few years, and then cooled and formed the islands of Hawaii. Hawaii is now the 50th state of the USA, but before the 21st of August 1959, was a whole country.
There are different types of volcanoes. One is the Compound Volcano, which explodes violently when it erupts, throwing ash and rock far into the air. Another is the Cinder Cone Volcano, where the lava is thick and cools around the rim, forming a tall, steep mountain. Shield volcanoes have runnier lava, which trickles down the sides quickly. An underwater shield volcano created the islands of Hawaii.
On the cold, outer planets and moons of the solar system, there are even Cryovolcanoes, which erupt liquid methane instead of lava. The biggest volcano in the solar system is actually a shield volcano on Mars, which is over two times taller than Mount Everest. The dangers are still there though; tsunamis, piroclastic flows, toxic gas - even if there aren’t any people.
Yellowstone National Park, USA. 640K years ago.
This eruption was not like any other - in the rare occasion of a supervolcano erupting, such as this one, you will definitely need to evacuate; maybe even to another planet. The whole of America was trashed, covering the whole continent with lava and clearing all the visability from sight. But let’s not forget about the rest of the world - what happened to that? On the south side of things, South American and African farmers were dishearted to see all their crops burn to death, but probably didn’t expect their own deaths! Otherwise, the north wasn’t going easy either. The ash even reached Russia and Svalbard, Norway, but the only thing that hadn’t reached Russia was civilization!
Mount Vesuvius, Italy. 79 AD.
You’ve probably been taught this at school a few weeks ago, but here’s a recap. It happened on the 24th of August 79 AD, where it started off regular, but with a few normal tremors. When it had reached 10am, people started to notice animals fleeing and the ground shaking. At lunchtime, ash was really starting to pile up and the tiles and plastering were falling off at a rapid pace. Then by 2pm, oh my! Fires rose up to 3 metres and the properties were already reduced to rubble. But then at evening, it was too late for the people to flee, as the lava had killed them before.
Krakatoa, Indonesia. Late 1800s.
This was a volcano on an island. The eruption killed thousands of people nearby, but also caused huge landslides into the sea, creating massive tsunamis that swept across the sea, killing thousands more people. The eruption was so bigger, it could even be detected on the other side of the world.
Underwater Shield Volcano, in what is now Hawaii. 4.5 Million Years ago.
This seemingly ordinary underwater shield volcano in the Pacific ocean had never exploded, until, in one of the biggest eruptions yet, pushed up literally millions of tonnes of rock, ash and pumice up to the surface, where it drifted there for a few years, and then cooled and formed the islands of Hawaii. Hawaii is now the 50th state of the USA, but before the 21st of August 1959, was a whole country.
At last a blog that I can follow and actually learn something. The article is clear and concise.
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