How deadly, fast-moving flows of volcanic rock and gas cheat friction
Lab experiments show the mixtures travel so far and so fast by riding on air
![Pyroclastic flow in an eruption](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2019/04/040519_mt_pyroclastic-flow_feat.jpg?fit=860%2C460&ssl=1)
FAST FLOW Simulating avalanches of volcanic material called pyroclastic flows in the lab show how these currents cover so much ground.
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