How pyroclastic flows seem to defy friction Apr 9, 2019 10:30 am by news@illinois.eduIllinois in the News Share on Facebook Tweet Email Images Volcanologists have long been baffled by the way pyroclastic flows seem to defy friction. But in a study published in the journal Nature Geoscience, a team of scientists has finally pulled back the curtain on these catastrophic currents. Share on Facebook Tweet Email