Physical/chemical properties of gas hydrates and application to world margin stability and climatic change
Sloan, E.D. (1998). Physical/chemical properties of gas hydrates and application to world margin stability and climatic change, in: Henriet, J.-P. et al. Gas hydrates: relevance to world margin stability and climate change. Geological Society Special Publication, 137: pp. 31-50. https://dx.doi.org/10.1144/GSL.SP.1998.137.01.03 In: Henriet, J.-P.; Mienert, J. (1998). Gas hydrates: Relevance to world margin stability and climate change. Geological Society Special Publication, 137. The Geological Society: London. ISBN 1-86239-010-X. 338 pp., more In: Hartley, A.J. et al. (Ed.) Geological Society Special Publication. Geological Society of London: Oxford; London; Edinburgh; Boston, Mass.; Carlton, Vic.. ISSN 0305-8719; e-ISSN 2041-4927, more |
| Keywords | Chemical compounds > Organic compounds > Hydrocarbons > Gas hydrates
Climatic changes
Plate margins
Properties > Chemical properties
Properties > Physical properties
Stability
Marine/Coastal |
| Abstract | The major points in this paper concern: (a) physical and chemical properties and (b) applications of those properties. Three questions are addressed: What are hydrates? What is our knowledge about their thermodynamic and kinetic properties? What are the applications to the environment and climate stability?The physical and chemical characteristics of hydrates are approximated by three heuristics: (1) physical properties approximate those of ice, (2) phase equilibrium characteristics are set by the size ratio of guest within host cages, and (3) thermal properties are set by hydrogenbonded crystals with cavity size ratios. Knowledge of hydrate kinetics is substantially lacking, but it appears that formation kinetics derive from aggregation of water clusters at interfaces. A significant future challenge is to characterize hydrates directly (through NMR, Raman, diffraction, etc.) for both thermodynamics and kinetics.Hydrocarbons in natural hydrates represent twice the amount of all combined fossil fuels. Most recovered samples have been small, dispersed (even dissociated) particles with isolated examples of massive hydrates. Hydrates probably will not contribute significant methane to the atmosphere in the near future. Ocean hydrates and air hydrates from Antarctic ice are indicators of ancient climatic changes. |
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