In 1934, Hammerschmidt showed that the formation of gas  hydrates  was responsible for blocking pipelines. Considering the significant economic risks in the gas and oil industry, much of research has been conducted by the petroleum industry in order to inhibit this phenomenon.

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Clathrate hydrates (or gas clathrates, gas hydrates, clathrates, hydrates, etc.) are crystalline water-based solids physically resembling ice, in which small non polar molecules (typically gases) are trapped inside "cages" of hydrogen bonded water molecules. In other words, clathrate hydrates are clathrate compounds in which the host molecule is water and the guest molecule is typically a gas. Without the support of the trapped molecules, the lattice structure of hydrate clathrates would collapse into conventional ice crystal structure or liquid water. Most low molecular weight gases (including O2, H2, N2, CO2, CH4, H2S, Ar, Kr, and Xe), as well as some higher hydrocarbons and freons will form hydrates at suitable temperatures and pressures. Clathrate hydrates are not chemical compounds as the sequestered molecules are never bonded to the lattice. The formation and decomposition of clathrate hydrates are first order phase transitions, not chemical reactions.