flammable solid similar to ice
"Burning ice". Methane, released by heating, burns; water drips. Inset: clathrate structure (University of Göttingen, GZG. Abt. Kristallographie). Source: United States Geological Survey.
Methane clathrate (CH4·5.75H2O) or (4CH4·23H2O), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, methane gas, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice. Originally thought to occur only in the outer regions of the Solar System, where temperatures are low and water ice is common, significant deposits of methane clathrate have been found under sediments on the ocean floors of the Earth (around 1100 m below the sea surface). Methane hydrate is formed when hydrogen-bonded water and methane gas come into contact at high pressures and low temperatures in oceans.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).