Mystery #2Tier 2earth / volcanoes
Why does a mountain suddenly blast out red-hot rock?
A volcano can sit quietly for years, looking like an ordinary mountain you could climb. Then, without much warning, it splits open and hurls out rivers of glowing, red-hot rock, hot enough to set trees alight. Where does a cold-looking mountain suddenly find liquid fire deep enough inside it to blast out of the top?
Your guess
What do you reckon is going on deep inside a volcano before it erupts?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
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