thumb|The ten-day phreatomagmatic eruption that formed the [[Ukinrek maars]] thumb|The Devil Mountain Lakes on the Seward Peninsula in western Alaska – the largest maar-based lakes in the world
thumb|The ten-day phreatomagmatic eruption that formed the [[Ukinrek maars]] thumb|The Devil Mountain Lakes on the Seward Peninsula in western Alaska – the largest maar-based lakes in the world
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow crater lake, which may also be called a maar.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).