plural of pyroclast

(volcanology) Mostly composed of rock fragments of volcanic origin or comminuted during an eruption.

A rock mostly composed of rock fragments of volcanic origin

(geology) Solid matter ejected into the air by an active volcano.

plural of pyroclastic

(volcanology) A dense flow of volcanic ash, dust, rocks and debris that cascades at high speed down the slope of a volcano during an eruption.

(volcanology) A fluidized mass of turbulent gas and rock fragments which is ejected during some volcanic eruptions.

(volcanology) Any rock formed by the accumulation of fragmented volcanic material (pyroclasts) ejected during explosive eruptions.

plural of pyroclastic flow

plural of pyroclastic surge