How is methane ice different from water ice?

Huge amounts of methane are being found on the ocean floor, trapped within cages of water molecules. Methane clathrate, also called methane hydrate or methane ice, is a solid form of water that contains a large amount of methane within its crystal structure (a clathrate hydrate). read more

In a sense, they're the same thing, in different forms. They're different in the way the molecules are organized. They're more orderly in Ice (created by either very strong pressure (you'd need an ocean deeper than the Earth's ocean for it) or cold) and transient in Water. read more

Methane clathrate (CH 4 ·5.75H 2 O) or (4CH 4 ·23H 2 O), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, 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. read more