Subproject A4 Numerical Modelling

The formation of submarine gas hydrates and their spatial distribution in the subsurface depends on a variety of sensitive control parameters, e.g. the in-situ production of methane, the advection of dissolved and gaseous methane, the existence of fluid pathways as well as the porosity and permeability of sediments. Hence, the quantification of gas hydrate inventories is still largely unconstrained in most regions. This project aims at the numerical simulation of potential gas hydrate reservoirs for selected, well-known locations to predict their 3-D-distribution within the sedimentary sequence. In addition, we plan to give constraints on the long-term stability of gas hydrate reservoirs in order to get a better understanding of their temporal dynamics.

Methods
The numerical model „PetroMod“ (IES company), a standard exploration tool in the oil and gas industry will be used to develop a new, 3-D-model for the simulation of sub-seafloor gas hydrate occurrences. A major task is the implementation of biogeochemical approaches with respect to gas hydrate formation / dissolution as well as the temporal and spatial resolution of the basis model. This approach will particularly enhance our knowledge with regard to the simulation of pathways for fluid and gas transport in consolidated sediments and hence, the potential enrichment of gas hydrates within certain sedimentary strata.

Literatur

AuthorTitleYearJournal/ProceedingsReftypeDOI/URL
Clennell, M., Hovland, M., Booth, J.S., Henry, P. & Winters, W.J. Formation of natural gas hydrates in marine sediments 1. Conceptual model of gas hydrate growth conditioned by host sediment properties 1999 Journal of Geophysical Research-Solid Earth
Vol. 104(B10), pp. 22985-23003 
article  
Haeckel, M., Boudreau, B.P. & Wallmann, K. Bubble-induced porewater mixing: A 3-D model for deep porewater irrigation 2007 Geochimica et Cosmochimica Acta
Vol. 71, pp. 5135–5154 
article DOI  
Haeckel, M., Suess, E., Wallmann, K. & Rickert, D. Rising methane gas bubbles form massive hydrate layers at the seafloor 2004 Geochimica Et Cosmochimica Acta
Vol. 68(21), pp. 4335-4345 
article DOI  
Hensen, C. & Wallmann, K. Methane formation at Costa Rica continental margin - constraints for gas hydrate inventories and cross-decollement fluid flow 2005 Earth and Planetary Science Letters
Vol. 236(1-2), pp. 41-60 
article DOI  
Luff, R. & Wallmann, K. Fluid flow, methane fluxes, carbonate precipitation and biogeochemical turnover in gas hydrate-bearing sediments at Hydrate Ridge, Cascadia Margin: Numerical modeling and mass balances 2003 Geochimica Et Cosmochimica Acta
Vol. 67(18), pp. 3403-3421 
article DOI  
Milkov, A.V. Molecular and stable isotope compositions of natural gas hydrates: A revised global dataset and basic interpretations in the context of geological settings 2005 Organic Geochemistry
Vol. 36(5), pp. 681-702 
article DOI  
Schmidt, M., Hensen, C., Morz, T., Muller, C., Grevemeyer, I., Wallmann, K., Mau, S. & Kaul, N. Methane hydrate accumulation in "Mound 11" mud volcano, Costa Rica forearc 2005 Marine Geology
Vol. 216(1-2), pp. 83-100 
article DOI  
Sloan, E.D.J. & Koh, C. Clathrate hydrates of natural gases 2008 , pp. 537-628  inbook URL 
Tishchenko, P., Hensen, C., Wallmann, K. & Wong, C.S. Calculation of the stability and solubility of methane hydrate in seawater 2005 Chemical Geology
Vol. 219(1-4), pp. 37-52 
article DOI  
Torres, M.E., Wallmann, K., Trehu, A.M., Bohrmann, G., Borowski, W.S. & Tomaru, H. Gas hydrate growth, methane transport, and chloride enrichment at the southern summit of Hydrate Ridge, Cascadia margin off Oregon 2004 Earth and Planetary Science Letters
Vol. 226(1-2), pp. 225-241 
article DOI  
Tréhu, A., Torres, M., Bohrmann, G. & Colwell, F. Leg 204 synthesis: Gas hydrate distribution and dynamics in the central Cascadia accretionary complex. 2006 Proceedings of the Ocean Drilling Program, Scientific Results, pp. 1-41  incollection DOI  
Wallmann, K., Aloisi, G., Haeckel, M., Obzhirov, A., Pavlova, G. & Tishchenko, P. Kinetics of organic matter degradation, microbial methane generation, and gas hydrate formation in anoxic marine sediments 2006 Geochimica Et Cosmochimica Acta
Vol. 70(15), pp. 3905-3927 
article DOI  
Wellsbury, P., Goodman, K., Barth, T., Cragg, B.A., Barnes, S.P. & Parkes, R.J. Deep marine biosphere fuelled by increasing organic matter availability during burial and heating 1997 Nature
Vol. 388(6642), pp. 573-576 
article URL