This paper examines the maximal extent of shallow thermal gradient distortions brought about by hydrate rich regions of finite lateral dimensions in sediments. In general, the anomalous gradient depends on both the thickness of the hydrate layer, the fraction of hydrate in the pore space and the lateral dimensions of the hydrate-bearing body. It is shown that it is difficult to obtain more than about a 5 to 10 percent change in the regional temperature gradient for hydrate fractions of up to 35%-near the maximum of observed values. The identification of hydrate bodies by use of shallow thermal gradient probes would, therefore, seem to be difficult but not impossible.
References
1.
AllisonE. C.ByerC. W.GuthrieH. D., and MrozT. H., 2000, Hydrates: Next Great Energy Source? The American Oil and Gas Reporter, pp. 198–201, 2000.
2.
CarcioneJ. M., and TinivellaU., 2000, Bottom Simulating Reflectors: Seismic velocities and AVO effects, Geophys. 65, 54–67.
3.
CollettT. W., 2000, Natural Gas Hydrates: Resource of the 21st Century? Paper presented at Pratt II Conference “Petroleum Provinces of the 21 st Century”, 12–15 January, San Diego, 64 p.
4.
GinsburgG. D., and SolovievV. A., 1998, Submarine Gas Hydrates, VNIIOkeangeologia, Saint Petersburg (English translation courtesy of STATOIL), 215 p.
5.
HowellD. G., (ed.), 1993, The Future of Energy Gases, U. S. Geological Survey Professional Paper 1570, United States Government Printing Office, Washington, D. C., 890 p.
6.
HuntJ. M., 1979, Petroleum Geochemistry and Geology, W. H. Freeman and Co., San Francisco, 617 p.
7.
KaplanI. R., (ed.), 1974, Natural Gases in Marine Sediments, Plenum Press, New York, 324 p.
8.
LaherrereJ. H., 2000, Oceanic Hydrates: Where, How, and How Much?This issue of Energy Exploration & Exploitation.
9.
LercheI., 2000, Estimates of Worldwide Gas Hydrate Resources, This issue of Energy, Exploration & Exploitation.
10.
LercheI., and O'BrienJ. J., (eds.), 1986, Dynamical Geology of Salt and Related Structures, Academic Press, San Diego, 832 p.
11.
LercheI., and PetersenK., 1995, Salt and Sediment Dynamics, CRC Press, Boca Raton, 322 p.
12.
MakogonY. F., 1997, Hydrates of Hydrocarbons, Penwell Publishing Co., Tulsa, 482 p.
13.
MorseP. M., and FeshbachH., 1953, Methods of Theoretical Physics, McGraw-Hill Book Co., New York, 997 p.
14.
SloanE. D.BrewerP. G.CollettT. S.DillonW. P.HolbrookW. S.KvenvoldenK. A., and PaullC. K., 2000, A Gas Hydrate Research Program, Report of a meeting at Golden, Colorado on 20–21 February, 2000. Available from the Internet under http://www.mines.edu/research/chs/plan.html.
15.
VogtP. R.CherkashevG.GinsburgG.IvanovG.MilkovA.CraneK.LeinA.SundvorE.PimenovN., and EgorovA., 1997, EOS Transactions, 48, 549–557.
