What causes volcanic eruptions and where do they usually occur?

Volcanic eruptions happen when molten rock, called lava, bursts out from deep inside the Earth and comes up to the surface.

Imagine the Earth is like a big chocolate cake, warm on the inside and cool on the outside. Inside this cake are layers of hot stuff that can move around. When these layers get too hot and pressurized, they push upward like a pressure cooker about to explode. This pressure makes the lava rush up through cracks in the Earth's surface, causing an eruption.

Volcanoes usually pop up along edges of tectonic plates, which are like giant puzzle pieces that make up the Earth’s crust. These plates move slowly, sometimes bumping into each other or sliding past one another.

When two plates move apart, like a zipper opening, hot material from deep inside the Earth can rise through the gap and create new land, this is where volcanoes often form. You can think of it as a hot lava fountain between two moving pieces of floor!

Sometimes, these plate movements cause big shake-ups, which are earthquakes, and then lava flows out like a molten river from a volcano.