Hydrate resource

The Beaufort-Mackenzie Basin hosts immense unconventional natural gas hydrate reserves that are often co-located with conventional petroleum resources. Osadetz et al. (2005) reported that the conventional resources are co-located with an immense gas hydrate resource estimated between 2.4 x 1012 and 87 x 1012 m3 of raw natural gas. Because the expected decline in conventional natural gas production from the Western Canada Sedimentary Basin cannot be replaced by conventional production from frontier regions alone, this immense hydrate resource offers a solution to replace the expected decline in conventional gas reserves. 

The key to establishing gas hydrates as a significant energy resource is whether the methane gas will ever be economically and safely producible. The current state of knowledge is still too limited to allow reliable estimates on the start of an economic gas hydrate production. The BGR (2003) estimates gas hydrate resources at 500 Tm3. 

Makogon (1965) announced the presence of gas hydrates in the permafrost regions of the Soviet Union. Since that time there have been two extreme views of in situ hydrate reserves. In one view, they have been ignored, presumably because they were considered to be too dispersed and difficult to recover, relative to the conventional supply of gas. In the other view, they were thought to be pervasive in all regions of the earth with permafrost (23% of the land mass) and in thermodynamically stable regions of the oceans (90% of the oceans areal extent). With further exploration and production of gas from a hydrate reservoir, a third, more realistic estimate of the hydrate resource has evolved, as the basis for this chapter. 

The most detailed method of U.S. hydrate resource estimation has been by Collett (1995, 1996). He assigned probabilities to 12 different factors to estimate the hydrate resources within the United States at 9 x 1015 m3 of gas. Collett (1995) notes the high degree of uncertainty places the above mean value between the 95% probability level (3x 1015 m3) and the 5% probability level (19x 1015 m3). However, in the United States, the mean hydrate value indicates 300 times more hydrated gas than the gas in the total remaining recoverable conventional reserves. 

The numbers for the United States are as follows. The U.S. Geological Survey (USGS) released a report in 1995 evaluating the U.S. hydrate resource base. It categorized estimates by the level of certainty that they exist.23... 

Waseda A., Baba K, Yagi M., Matsumoto R., Lu H., Hiroki Y. and Fuin T. (1998) Geochemical characteristics of gases and sediments in the Nankai Trough, offshore Tokai. Proceedings of the International Symposium on Methane Hydrates Resources in the Near Future , Chiba, pp. 55-59. 

Proc. Int. Symp. on Methane Hydrates Resources in the Near Future National Oil Corporation Chiba, Japan. 

Calcium. Calcium is the fifth most abundant element in the earth s cmst. There is no foreseeable lack of this resource as it is virtually unlimited. Primary sources of calcium are lime materials and gypsum, generally classified as soil amendments (see Calcium compounds). Among the more important calcium amendments are blast furnace slag, calcitic limestone, gypsum, hydrated lime, and precipitated lime. Fertilizers that carry calcium are calcium cyanamide, calcium nitrate, phosphate rock, and superphosphates. In addition, there are several organic carriers of calcium. Calcium is widely distributed in nature as calcium carbonate, chalk, marble, gypsum, fluorspar, phosphate rock, and other rocks and minerals. 

Since methane is almost always a byproduct of organic decay, it is not surprising that vast potential reserves of methane have been found trapped in ocean floor sediments. Methane forms continually by tiny bacteria breaking down the remains of sea life. In the early 197Qs it was discovered that this methane can dissolve under the enormous pressure and cold temperatures found at the ocean bottom. It becomes locked in a cage of water molecules to form a methane hydrate (methane weakly combined chemically with water). This "stored" methane is a resource often extending hundreds of meters down from the sea floor. 

Gas hydrates are non-stoichiometric crystals formed by the enclosure of molecules like methane, carbon dioxide and hydrogen sulfide inside cages formed by hydrogen-bonded water molecules. There are more than 100 compounds (guests) that can combine with water (host) and form hydrates. Formation of gas hydrates is a problem in oil and gas operations because it causes plugging of the pipelines and other facilities. On the other hand natural methane hydrate exists in vast quantities in the earth s crust and is regarded as a future energy resource. 

Should for one reason or another the climate change issue disappear, there would only be a future for nuclear power if it can compete vis-a-vis combined cycle natural gas plants. At least for the next 50 years, there should be adequate gas resources and if gas hydrate deposits are taken into account, resources could last centuries. 

Osadetz, K.G., Morrell, G.R., Dixon, J., Dietrich, J.R., Snowdon, I.R., Dallimore, S.R., Majorowicz, J.A. 2005. Beaufort-Mackenzie Basin A review of conventional and nonconventional (gas hydrate) petroleum reserves and undiscovered resources. Geological Survey of Canada, Bulletin 585. 

Uddin, M., Coombe, D., Law, D., Gunter W,D. 2008a. Numerical studies of gas hydrate formation and decomposition in a geological reservoir. ASME, Journal of Energy Resources Technology, 130, paper 032501. 

Cui et al. performed similar analyses to fhose of Dupuis and co-workers. The side chain-side chain radial disfribufion functions (RDFs) reported by Cui et al. show remarkable qualitative deviation from fhose in Zhou et al. i It is of note that the united atom approach used by Cui and co-workers ignored electrostatic interactions between CP2 groups of the polymeric backbone. This can lead to a poor description of fhe hydrated structure in the regions close to the polymeric backbones, unlike the all-atom force field used in Zhou et al. ° For the sake of limited computational resources, Cui et al. used a relatively short representation of Nation ionomer chains consisting of three monomers as compared to the ten monomers used by Vishnyakov and Neimark or Urata et al. It can be expected that structural correlations will strongly depend on this choice. 

Natural gas (methane) can be obtained from gas hydrates. Gas hydrates are also called clathrates or methane hydrates. Gas hydrates are potentially one of the most important energy resources for the future. Methane gas hydrates are increasingly considered a potential energy resource. Methane gas hydrates are crystalline solids formed by combination of methane and water at low temperatures and high pressures. Gas hydrates have an iee-hke crystalline lattiee of water molecules with methane molecules trapped inside. Enormous reserves of hydrates can be foimd imder eontinental shelves and on land under permafrost. The amount of organic... 

Gas hydrates were first reported at the beginning of the 19th century, and until the 1930s they remained a scientific curiosity. At that time it was realized that hydrates were more likely to be the causative agent in blocking pipelines than ice. Today, gas hydrate control continues to be a problem in the oil and gas industry. In the 1960 s it was realized that natural gas hydrates are present in the geo-sphere with worldwide reserves estimated at 10,000 to 40,000 trillion cubic meters (TCM). Considerable efforts are underway to refine global estimates and to develop technology and exploit this resource. On the other hand these hydrates may... 

Max et al. (2006) discuss the issue of gas hydrates as an energy resource extensively in a recent publication. 

Collett, T.S. (2005). Results at Mallik highlight progress in gas hydrate energy resource... 

Scholz. C. and R. Gross, el al. Polymers from Benenable Resources Carht>hydrates and Agrrsproteites, Oxford University Press. New YoA. NY. 2000. 

Studies of obsidian artifacts and sources can be used to examine resource procurement patterns, to identify long-distance exchange networks, to study manufacturing processes, and to establish site chronologies. In addition, obsidian artifacts may be used to extract dating information through hydration dating. 

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