Clouds of rocks and gas known as pyroclastic flows spew out of volcanoes and race over land at terrifying speeds, skating on an air pocket beneath the rubble
Source: https://www.newscientist.com/article/2198735-hot-rubble-from-volcanoes-races-over-land-on-a-carpet-of-air-bubbles/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home