What are submarine eruptions?

Submarine eruptions are volcanoes that explode underwater, sending hot lava into the cold ocean.

Imagine blowing bubbles into a glass of water. The bubbles rise and pop. Now imagine the water is boiling hot and the air is super thick. That is what happens when magma meets the sea. The hot rock from deep inside the Earth pushes up through the ocean floor. Because the water is so cold and heavy, the lava cools down very fast. It does not flow like honey. Instead, it forms smooth, blobby shapes called pillow lava. These look like giant pillows or round bread rolls sitting on the sea bed.

The ocean acts like a giant freezer for the fire.

These underwater volcanoes are busy builders. Over many years, piles of cooled lava grow bigger and bigger. If they grow high enough, they can poke out of the water to form new islands. You can think of it like stacking wet sand. If you keep adding wet sand, the pile gets taller until it is high enough to stay dry. Submarine eruptions are nature’s way of making new land from the deep sea.

So, a submarine eruption is simply Earth’s way of baking giant lava bread rolls on the ocean floor, slowly building up until they become islands.