Pyroclastic
Pyroclastic materials are fragments of volcanic rock formed during explosive eruptions. These fragments can range in size from microscopic ash particles to large blocks and bombs. Pyroclastic flows are high-speed avalanches of hot ash, rock fragments, and gas that flow down the sides of a volcano during an eruption. Pyroclastic surges are less dense, turbulent clouds of hot gas and ash that can travel at high speeds across the ground. Pyroclastic fall refers to ash and other volcanic debris that is ejected into the atmosphere during an eruption and then falls back to the ground. Overall, pyroclastic materials are a key characteristic of explosive volcanic activity.