Of methane hydrates

In 1970 a huge deposit of methane hydrate was discovered at the bottom of the Atlantic Ocean, 330 km off the coast of North Carolina. 

On the Internet, research one possible structure of methane hydrate. Create a physical model or a three-dimensional computer model to represent it. Use your model to explain why methane hydrates are unstable at temperatures that are warmer than 0°C. 

Circone, S. Kirby, S.H. Stem, L.A. (2005). Direct measurement of methane hydrate... 

Gayet, P. Dichany, C. Marion, G. Graciaa, A. Lachaise, J. Nesterov, A. (2005). Experimental determination of methane hydrate dissociation curve up to 55 MPa by using a small amount of surfactant as hydrate promoter. Chem. Eng. Sci., 60 (21), 5751-5758. 

Glasby, G.P. (2003). Potential impact on climate of the exploitation of methane hydrate deposits offshore. Marine Petroleum Geology 20 (2), 163-175. 

Hwang, M.J. Wright, D.A. Kapur, A. Holder, G.D. (1990). An experimental study of crystallization and crystal growth of methane hydrates from melting ice. J. Incl. PhenomMol. Recog. Chem., 8, 103-116. 

Klauda, J., B. Sandler, S.I. (2005). Global distribution of methane hydrate in ocean... 

Kumazaki, T. Kito, Y. Sasaki, S. Kume, T. Shimizu, H. (2004). Single-crystal growth of the high-pressure phase II of methane hydrate and its Raman scattering study. Chem. Phys. Letter, 388 (1-3), 18-22... 

Machida, S. Hirai, H. Kawamura, T. Yamamoto, Y. Yagi, T. (2006). A new high-pressure structure of methane hydrate surviving to 86 GPa and its implications for the interiors of giant icy planets. Physics of the Earth and Planetary Interiors, 155 (1-2), 170-176. 

Uchida, T. Hirano, T. Ebinuma, T. Narita, H. Gohara, K. Mae, S. Matsumoto, S. (1999a). Raman spectroscopic determination of hydration number of methane hydrates AIChEJ., 45 (12), 2641-2645. 

Wang, X. Schultz, A. Halpem, Y. (2002). Kinetics of methane hydrate formation from polycrystalline deuterated ice. J. Phys. Chem. B, 106 (32), 7304-7309. 

Wilson, L. D. Tulk, C. A. Ripmeester, J. A. (2002). Instrumental Techniques for the Investigation of Methane Hydrates Cross-calibrating NMR and Raman Spectroscopic Data. Proc. 4th Int. Conf. Gas Hydrates, 2, 614-618. 

Yoon, J.-H. Kawamura, T. Yamamoto, Y. Komai, T. (2004). Transformation of Methane Hydrate to Carbon Dioxide Hydrate In Situ Raman Spectroscopic Observations. J. Phys. Chem. A, 108, 5057-5059. 

Figure 6 ESR spectrum of methane hydrate irradiated by x-rays at 11 K. Methyl radicals and hydrogen atoms in synthetic methane hydrates (Takeya et al., 2004).,m...

Hydrate clathrates of organic compounds are thought to be responsible for the behavior of ice in the heads of comets and in wet methane under pressure.22 Unless methane is carefully dried, high-pressure lines may become clogged with the ice-like gas hydrate. There may be large deposits of methane hydrates, the ice that burns. beneath the ocean floor. 

These include (1) tight sandstones, (2) Devonian shales. (3t geopiessured zones, (4) deep basins, (5) gas associated with coal seams, and (6) gas in the form of methane hydrates. 

Dyadin et al. discover a very high pressure phase of methane hydrate that is stable up to 600 MPa... 

While si, sll, and sH are the most common clathrate hydrates, a few other clathrate hydrate phases have been identified. These other clathrate hydrates include new phases found at very high pressure conditions (i.e., at pressures of around 1 GPa and higher at ambient temperature conditions). Dyadin et al. (1997) first reported the existence of a new methane hydrate phase at very high pressures (500 MPa). This discovery was followed by a proliferation in molecular-level studies to identify the structure of the high pressure phases of methane hydrate (Chou et al., 2000 Hirai et al., 2001 Kurnosov et al., 2001 Loveday et al., 2001, 2003). 

Kim, H.C., A Kinetic Study of Methane Hydrate Decomposition, Ph.D. Thesis, University of Calgary, Alberta (1985). 

Rueff, R.M., The Heat Capacity and Heat of Dissociation of Methane Hydrates A New Approach, Disssertation, Colorado School of Mines, Golden, CO (1985). 

Pandit and King (1982) and Bathe et al. (1984) presented measurements using transducer techniques, which are somewhat different from the accepted values of Kiefte et al. (1985). The reason for the discrepancy of the sonic velocity values from those in Table 2.8 and above is not fully understood. It should be noted that compressional velocity values can vary significantly depending on the hydrate composition and occupancy. This has been demonstrated by lattice-dynamics calculations, which showed that the adiabatic elastic moduli of methane hydrate is larger than that of a hypothetical empty hydrate lattice (Shpakov et al., 1998). 

Shimizu et al. (2002) extended the previous Brillouin spectroscopy measurements by performing in situ measurements on a single crystal methane hydrate. They examined the effect of pressure on shear (TA) and compressional (LA) velocities, and compared these results to that for ice. The shear velocities of methane hydrate and ice were very similar, showing a slight decrease (about 2 to 1.85 km/s) with increasing pressure (0.02-0.6 GPa). Conversely, the compressional velocities of ice and methane hydrate were different. The... 

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