The objective of this work was to enhance understanding of gas hydrate dissociation, and provide information to help evaluate gas hydrate processes, such as ocean CO2 sequestration and CH4 recovery from natural gas hydrates in deep sea sediments. The composition and dissociation behavior of CH4 + C2H6 and CH4 + CO2 structure I binary gas hydrates were determined using NMR spectral analysis. Single-pulse excitation was used in combination with magic-angle spinning (MAS). Time-resolved decomposition experiments were carried out on sealed, pressurized samples of both binary gas hydrate systems. Decomposition profiles have been obtained for each case. At the experimental conditions of this work, the gas hydrate composition did not change after the dissociation experiments. These results suggest that the unit cell decomposes as a single entity. (c) 2007 Elsevier B.V. All rights reserved.