W
inds howl. Blinding snow swirls. It’s
freezing here in Antarctica. You take a few steps forward. Suddenly, a blast of hot air hits your face. You see steam rising from the snow. You wonder why there’s steam in one of
the coldest places on Earth. It turns out you’re standing on a volcano. In fact, Mt. Erebus may be one of the world’s oddest volcanoes. T is volcano doesn’t blow its rocky top.
Rivers of red-hot lava don’t flow down its sides. Instead, the lava piles up inside the crater, or opening at its top. Look over the edge of the crater. You’ll see a huge, glowing lake of lava. T ere, this hot melted rock boils, burps, and bubbles. A stench that smells like rotten eggs rises. T is stink comes from sulfur in the lava. Heat from the lava lake sends curtains of
steam rising into the cold air. It’s not a good place to warm up, though. Sometimes, globs of lava fly into the air. T ey land with a sizzle.
Fire and Ice T e volcano’s steam melts nearby ice. It creates an amazing landscape. It hollows out ice caves on the slopes of the volcano. You crawl inside one. It feels a bit warmer here, but barely. Ice crystals decorate the cave walls. Sun shines through the ice, filling the cave with an eerie blue light. Outside the cave, hundreds
of icy chimneys rise. T ey’re on top of the volcano’s many vents. Vents are like pipelines that go deep into the volcano. Hot gases and steam rise through them. When the steam hits the cold air, it freezes. It builds icy towers. up to 18 m tall.
18 NATIONAL GEOGRAPHIC EXTREME EXPLORER
What Lies Beneath Mt. Erebus may be an icy oddity. Yet in some ways, it’s like many other volcanoes. Like them, its heat starts in Earth’s core, deep in the center of our planet. T is heat spreads to the next layer of Earth, the mantle. T ere, it melts some rocks until they ooze like thick honey. T is oozing magma pushes against Earth’s
rocky top layer, the crust. T is layer is made up of giant chunks of land called tectonic plates. Magma flows through the cracks between the plates. It pushes up and up. Eventually, it reaches Earth’s surface. Hot, liquid rock erupts out of the ground.
Now it’s called lava. It hardens as it cools. Layer by layer, it builds a volcano. Most volcanoes form in specific places. You
can find them along the boundaries, or edges, of the giant plates. Mt. Erebus is diff erent. It rises from the middle of one of these plates. Here, the pressure of rising magma is so great that it pushes right up through the crust. Rising magma built four volcanoes. T ree
don’t erupt any more. T ey may be dormant, or sleeping. Or they may be extinct and will never erupt again. Mt. Erebus remains active. Its lava lake may keep bubbling for years to come.
Steam from Mt. Erebus carved this cave.
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