Gas hydrates are a crystalline solid formed of water and gas. It looks and acts much like ice, but it contains huge amounts of methane; it is known to occur on every continent; and it exists in huge quantities in marine sediments in a layer several hundred meters thick directly below the sea floor and in association with permafrost in the Arctic. It is not stable at normal sea-level pressures and temperatures, which is the primary reason that it is a challenge to study.
Gas hydrates are important for three reasons:
- They may contain a major energy resource
- It may be a significant hazard because it alters sea floor sediment stability, influencing collapse and landsliding
- The hydrate reservoir may have strong influence on the environment and climate, because methane is a significant greenhouse gas.