An ice–marginal lava flow is a lava flow that has impounded against a glacier

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

, ice sheet

Ice sheet

An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km² , thus also known as continental glacier...

, ice field

Ice field

An ice field is an area less than 50,000 km² of ice often found in the colder climates and higher altitudes of the world where there is sufficient precipitation. It is an extensive area of interconnected valley glaciers from which the higher peaks rise as nunataks...

 or any other body of glacial ice. They commonly display steep lava cliffs from their interaction with glacial ice and can have thicknesses of 100 m (328.1 ft). Columnar joints with unique patterns can form by rapid cooling of the lava. Ice–marginal lava flows are products of glaciovolcanism

Glaciovolcanism

Glaciovolcanism is a term used to describe volcanism and related phenomena associated with glacial ice. The ice commonly constrains the erupted material and melts to create meltwater. Considerable melting of glacial ice can create massive lahars and glacial outburst floods known as jökulhlaups...

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