Solved cryptogram
The lethal part of an eruption is often not the lava but a hot cloud that races downhill.
Earth Science Facts, sourced to U.S. Geological Survey.
Solve it yourself
This fact is a cryptogram here: 71 letters over 18 different ones, graded medium.
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What it means
Lava usually moves slowly enough to walk away from. A pyroclastic flow is a ground hugging avalanche of gas, ash and rock fragments that pours off a collapsing eruption column at highway speeds and at several hundred degrees. It flattens forests, crosses water and leaves nothing alive in its path. This is what buried Pompeii and Herculaneum, and it is why volcano hazard maps are drawn around valleys rather than around the summit.
The claim comes from U.S. Geological Survey.
- SourceU.S. Geological Survey
- CollectionEarth Science Facts
- Difficultymedium
- Length71 letters, 18 of them different
Nearby in the collection
The facts either side of this one.
- U.S. National Park Servicemedium, 77 letters
- U.S. National Park Servicemedium, 73 letters
- U.S. Geological Surveymedium, 74 letters
- U.S. Geological Surveyhard, 75 letters
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