What’s the difference between magma and lava?
Magma is below the Earth. But when this molten rock find its way to the surface, it’s lava.
It’s when pressure builds up, volcanoes erupt. Magma spews from the planet interior to surface.
Lava flows out the volcano and downhill. When it comes, it builds new land.
This is why volcanoes are vital to geologists. It’s because it’s the start of the rock cycle.
The anatomy of lava and magma
Magma is liquid rock with dissolved gas within the interior of the Earth. When magma reaches the surface, it’s lava.
Not only do volcanoes spew out lava, but also water. When gases get hot enough, they expand and explode.
But because water won’t sit on lava, it evaporates into a gas. Then, water vapor forms clouds.
Different kinds of volcanoes lock in different types magma underground. It’s the from the various types of magma that differentiate the types of volcanoes.
Igneous rocks from volcanoes
Volcanoes are the foundation for igneous rocks. Like a closed bottle of champagne, liquid rock pools in the magma chamber.
Once you pull the cork, the volcano erupts. It erupts from the expansion of gases from the mouth of the volcano.
Eventually, lava spews from the mouth. Like wax dripping down the side of a candle, igneous rocks like feldspars form.
So hot lava drips on the side of volcanoes then cools, hardens and become igneous rocks like granite. Without igneous rocks, there wouldn’t be the rock cycle.
The formation of volcanoes
Because divergent plates move apart from each other at these mid-oceanic ridges, magma flows upwards from the mantle beneath. When the lava hardens, it becomes dark igneous rock “basalt” at rift volcanoes.
When convergent plates collide, plates thrust upwards. Convergent boundaries has some of the most violent catastrophes and geology on Earth. When plates smash together, it has created chains of volcanoes.
Finally, volcanoes form at hot spot plumes. Like Hawaii, hot spot plumes rise through the mantle and melts when it reaches asthenosphere levels.