At river mile 179 Prospect Canyon enters on the south side of the river. At the foot of its debris fan sits Lava Falls. The Grand Canyon is a perfect setting for these debris fans. Debris flows are what create them, and these flows primarily occur in arid to semiarid environments.

Yes, lava waterfalls—often called "lavafalls"—are a real and spectacular volcanic phenomenon where molten rock flows over a cliff or steep drop, mimicking the appearance of a water-filled cataract. These are most commonly observed at "ocean entries," such as the famous Kamokuna lava delta at Hawaiʻi Volcanoes National Park, where Kilauea’s lava can form a "firehose" flow that pours directly into the sea. Inside volcanic craters, lavafalls can occur when an active flow spills over the rim of an inner pit or into a lava lake; a notable historic example occurred during Kilauea's 1969 eruption into the Alae Crater. Beyond Earth, the most extreme lavafalls in the solar system are found on Jupiter's moon, Io. In 1997, the Pillan Patera volcano produced a staggering 10,000-foot-high lavafall—nearly ten times the height of Earth's tallest water waterfall—cascading down a sulfur-covered cliff. Whether on Earth or Io, these features are ephemeral and highly dangerous, often accompanied by steam explosions and the release of toxic gases as the 2,000°F molten rock interacts with its surroundings.