In situ observation of hydrate growth habit in porous media using magnetic resonance imaging

To investigate the growth law and microstructure of hydrates in sediments, the growth process of the tetrahydrofuran (THF) hydrate is observed in site using magnetic resonance imaging (MRI). The hydrate formation starts preferentially from the grain surface and then grows towards the liquid phase filling up the pore. In the final stage, the hydrate cements and stiffens the sediment. In this study, the cementing microstructure of the THF hydrate was directly observed in porous media. The extension of the observed behavior to methane hydrates gives implications for understanding their role in the seismic exploration and the stability of permafrost and seafloor.