Australia has many dangers. Fires, floods, dangerous insects, terrifying temperatures, apocalyptic landscapes ... One of the few problems that this continent managed to avoid is volcanoes. There are no active volcanoes in Australia, but if you returned a few million years into the past, you would see a completely different picture.
A group of researchers announced the discovery of a chain of volcanoes - the largest ever found on the surface of the earth. The open circuit stretches across the continent up to Tasmania and has a length of more than 2 thousand kilometers.
Why were these volcanoes discovered just now? They are old and small and no longer spew lava. In fact, they look like this:
An open volcanic chain formed between 9 and 33 million years ago, when the Australian tectonic plate was moving above the hot spot.
Everything on Earth, from the mountains to the oceans, rests on a thin layer of fragile rock called the crust. This crust is divided into sections that move along the surface of a more flexible (and very hot) rock, called the mantle. But the mantle is not the same in different places on Earth. There are areas where it is much hotter. This heat is usually concentrated in a small area and melts the earth's crust like a soldering iron, creating a volcano in this place. While the terrestrial plates move, these points remain in the same places.
The volcano also moves along with the earth plate. He loses the heat source and gradually stops growing. Now the new section of the earth's crust is above the “hot spot”, and a new volcano begins to grow, becoming a satellite of an old extinct volcano.
This process continues as long as the plate moves over the hot spot, creating a long chain of volcanoes.
While the volcanic chain in Australia has become the largest known chain formed on the continent, it is not the largest on Earth. The longest chain of volcanoes lies at the bottom of the Pacific Ocean, forming the Hawaiian Islands. Its length is more than 6 thousand kilometers.
Based on Popular Science
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