Methane hydrate is crystallized water containing trapped methane which is found in the outer regions of space and deep in the ocean floor. It is represented by the chemical formula (CH4)4(H2O)23.
Other common names for methane hydrate include methane clathrate, hydromethane, natural gas hydrate, fire ice, methane ice and gas hydrate. Large deposits of methane hydrate have been found in the lithosphere, a part of the Earth's crust, in sedimentary rocks such as sandstone and siltstone. Commercial research on the uses of methane hydrate focuses on extracting natural gas from the crystal structure. Methane hydrate may also be formed during the production of natural gas when water condenses with high pressures of methane gas.