 Methane clathrates (also known as methane hydrates) are solid cages of water molecules that trap single molecules of methane.Significant reservoirs of methane clathrates have been found in arctic permafrost and along continental margins beneath the ocean floor within the gas clathrate stability zone, located at high pressures (1 to 100 MPa; lower end requires lower temperature) and low temperatures (< 15 °C; upper end requires higher pressure).Methane clathrates can form from biogenic methane, thermogenic methane, or a mix of the two.