Focused fluid flow systems in continental margins – Implications and recent advances

1. Focused fluid flow systems in continental margins – Implications and recent advances Christian Berndt oceansurv, Cowes, Isle of Wight Scientific targets and hydrocarbon industry relevance

2. Overview • Introduction • Focused fluid flow systems • Relevance of focused fluid flow systems • Seismic imaging • Gas hydrates • Volcanic intrusions • Geohazards • High-resolution 3D seismic acquistion system • Conclusions, outlook and possibilities for collaboration Scientific targets and hydrocarbon industry relevance

3. Fluid flow in passive margins Berndt, 2005 Scientific targets and hydrocarbon industry relevance

4. Why fluid flow research? • Fluid flow is the most important link from the subsurface to the seabed and many seabed processes cannot be understood without this link • Fluid flow/seepage and sedimentation are the two most important carbon fluxes from/to the geosphere • Fluid flow has important implications for hydrocarbon exploration and production, but it is only understood for very simple cases Fluid flow is highly relevant to society on a short term as opposed to many other geological processes Scientific targets and hydrocarbon industry relevance

5. Specific fields of research Fluid flow in passive margins is an important aspect of the Earth System • Fluid flow controls the release of carbon into the ocean and into the atmosphere • Fluid flow provides nutrients for chemosynthetic ecosystems • Fluids and gas migration poses the most dangerous hazard to offshore exploration and scientific ocean drilling • Fluid flow controls the distribution of natural energy resources (oil, gas, condensates, gas hydrates) Weaver et al., 2004 Scientific targets and hydrocarbon industry relevance

6. What does seafloor methane hydrate look like? • Methane hydrate (clathrate) • Methane (CH4) gas molecule trapped in lattice of water (H20) molecules • Dissociates (solid → gas) • High P, low T Pictures: IfM-Geomar Scientific targets and hydrocarbon industry relevance

7. United States Geological Survey Where do we find methane hydrates? Berndt et al. 2003 Scientific targets and hydrocarbon industry relevance

8. Geophysical response to gas hydrates • Gas hydrate quantification through • Seismic velocity response • Seismic attenuation • EM High Q = low Q-1 Western Svalbard Hydratech OBS tomography results, Rossi et al. (2007) Scientific targets and hydrocarbon industry relevance

9. Evidence for gas hydrates Vanneste et al., 2006 Scientific targets and hydrocarbon industry relevance

10. Intrusive volcanism in sedimentary basins • Break-up related volcanism • Sill intrusions into the sedimentary basins • Contact metamorphism releasing huge amount of carbon into the atmosphere • Early Eocene climate optimum Explosive eruption of greenhouse gas Formation of pipes and explosion craters Svensen et al. 2005 Scientific targets and hydrocarbon industry relevance

11. Distribution of vent complexes on the Norwegian Margin • 735 mapped • 2-3000 likely present • 1-2 km below the sea floor Mud volcanism in Azerbaijan as a modern analogue to gas explosions? (Photo: BBC, 2001) Svensen et al., 2004 Scientific targets and hydrocarbon industry relevance

12. Volcanic intrusions in the Faeroe Shetland Basin Vents in the Faeroe Shetland Trough Berndt and Hili, 2006 Scientific targets and hydrocarbon industry relevance

13. Free gas and slope stability linkage Masson and Berndt , 2006 Scientific targets and hydrocarbon industry relevance

14. Blow outs from free gas accumulations: A major geohazard • Gas blow-outs are the single biggest geohazard for the offshore industry • Every year blow-outs happen causing casualties • 3D imaging of shallow gas accumulations is necessary for avoiding blow-outs Scientific targets and hydrocarbon industry relevance

15. P-Cable projects • P-Cable is patented technology by VBPR • Joint development project involving VBPR, NOCS, UTromsoe, and IfM-Geomar • A seismic cable towed perpendicular to the vessel’s steaming direction • Many single-channel seismic streamers attached to a wire held in place by two doors Scientific targets and hydrocarbon industry relevance

16. Mercator Mud Volcano Gulf of Cadiz BSR Berndt et al., 2007 Scientific targets and hydrocarbon industry relevance

17. 3D visualisation Berndt et al., 2007 Scientific targets and hydrocarbon industry relevance

18. Overview • Introduction • Focused fluid flow systems • Relevance of focused fluid flow systems • Seismic imaging • Gas hydrates • Volcanic intrusions • Geohazards • High-resolution 3D seismic acquistion system • Conclusions, outlook and possibilities for collaboration Scientific targets and hydrocarbon industry relevance

19. Summary • Focused fluid flow systems are extremely relevant to society as they control our environment in the short term • Understanding the involved physical processes is instrumental for assessing their role in • climate change • chemosynthetic ecosystems • distribution of energy sources • geohazards (tsunamis, slides, etc.) Scientific targets and hydrocarbon industry relevance

20. Possible Collaborations • Influence of halokinesis on fluid migration patterns / cementation and drilling problems around salt diapirs • Effects of fluid migration/gas hydrates on sea bed stability • Mud volcanoes as a window to deeper hydrocarbon systems • Thermal structure from BSR depth • Effect of sill intrusions on sedimentary basins • Carbon sequestration • Site surveys Scientific targets and hydrocarbon industry relevance

21. Contact details Dr. Christian Berndt oceansurv 32 Denmark Road Cowes Isle of Wight PO31 7SZ United Kingdom cbe@noc.soton.ac.uk Consulting projects will be carried out by oceansurv. Scientific projects will be carried out either through National Oceanography Centre, Southampton, or IfM-Geomar, Kiel depending on project. Scientific targets and hydrocarbon industry relevance