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Although clathrates can theoretically form almost anywhere, in practice the largest deposits have been discovered in the oceans, on continental slopes and on land, in permafrost sedimentary basins.

No significant amounts of hydrates have yet been found in the open ocean, far from land. The deep ocean is too poor in organic matter for methane bacteria to find suitable living conditions. Furthermore, sediment accretion in the high seas is very slow – too little sediment sinks to the bottom to quickly cover and seal the gas reservoir.

The search for hydrates is facilitated by the unusual physical property of this substance – sound waves propagate through them at almost twice the speed of typical ocean sediments. This allows clathrates to stand out clearly on seismoacoustic cross-sections. Another feature of hydrates that facilitates the search is their ability to attenuate acoustic signals, known as blanking. The intensity of this attenuation is proportional to the methane content of the hydrate – this allows for the estimation of the deposit's resources.

Clathrate sources are primarily located using geophysical methods, with costly offshore drilling rarely performed. Traditional drilling is being replaced by less expensive sampling methods. This summer, the French research vessel Marion Dufrense extracted 25 50-meter-long cores in the Gulf of Mexico using a technique involving the insertion of a steel pipe into the seabed sediments. Deep-sea submersibles are also used to perform micro-drilling and collect samples. The Americans use a US Navy Alvin, while the Norwegians borrow Russian Mir submersibles.