Deep-water seafloor rendering and data extraction for environmental and geohazard assessment: A comparison study of 3D seismic reflection and multibeam sonar surface renders and amplitude backscatter
Lead PI: Dr. David Mosher
Subject Category: Other
Start Date: Dec 2001
End Date: Oct 2004
Institution / Organization: NRCan
Sunlight only penetrates the very shallowest, 100 metres of the ocean, cloaking most of the ocean floor in perpetual darkness and making it virtually impossible to take satellite images of the bottom of the ocean. Offshore industries build structures and pipelines on the ocean floor in order to extract oil & gas resources. To safely design and site these man-made structures requires detailed maps.
Ship survey technologies, using sound waves, are currently used to produce high quality images of the ocean floor in relatively shallow water, less than 300 metres. Offshore Nova Scotia and Newfoundland, oil and gas companies are now exploring in very deep waters (up to 3.5 km) where routine survey methods are not yet available.
A team of industry, government, and university researchers, led by Dr. David Mosher of the Geological Survey of Canada (Atlantic region), were funded through a two-year grant from Petroleum Research to evaluate seafloor surface topography data from two different survey techniques (multibeam sonar and 3-D seismic reflection). The data, collected from deep water environs offshore Nova Scotia, contributed to the research project by oil industry partners.
Early results suggested that, with proper analysis, these two techniques could be used to create the maps needed to site and design offshore oil & gas exploration structures in Atlantic Canada. The largest concern with both techniques was that they were underestimating slope angles on very steep inclines. Oil and gas production facilities may require still more detailed surveys with deep-tow or AUV technologies.
LaPierre, A.T., Cook, M., Mosher, D.C., Bigg, S. (2003) Re-Examining Deepwater Atlantic Canada: well technology & completion options. Energy Wise workshop: April 9 & 10, 2003, Halifax, NS
LaPierre, A.T., Mosher, D.C., Bigg, S. (2003) Imaging the seafloor in deep water - a comparison of 3D seismic reflection and multibeam sonar seafloor surface renders. Association of Canada Lands Surveyors in alliance with Canadian Hydrographic Association, Calgary, Alberta, 14 -15th October, 2003.
LaPierre, A.T., Mosher, D.C., Bigg, S., and Shylonyk, G. (2004) Comparison of 3D seismic reflection and multibeam sonar seafloor surface renders for deep water on the Scotian Slope: impact on seafloor process interpretations and geohazard evaluation. International Navigation Conference, Arab Institute of Navigation, Cairo, Egypt, April 2004
Mosher, D.C., LaPierre, A.T., Hughes-Clarke, J.E., and Gilbert, G.R. (2002) Theoretical comparison of seafloor surface renders from multibeam sonar and 3D seismic exploration data. Offshore Technology Conference Paper 14272, May 6-9, Houston, TX.
Mosher, D.C., LaPierre, A.T., and Bigg, S.E. (2002) A comparison study of 3D seismic reflection and multibeam sonar seafloor surface renders for deep water on the Scotian Slope. Offshore Technologies Association of Nova Scotia/CORE conference, October 2002, Program with Abstracts, p. 63.
Mosher, D.C., LaPierre, A.T., and Bigg, S.E., (2006) 3D seismic versus multibeam sonar sea-floor surface renderings for geohazard assessment; case examples from the central Scotian slope (in Geohazards and pore pressure prediction) Leading Edge (Tulsa, OK) (December 2006), 25(12): p.1484-1494
Mosher, D.C., LaPierre, A.T., Bigg. S.E., and Shylonyk, G. (2003) Comparison of 3d seismic reflection and multibeam sonar seafloor surface renders for deep water on the Scotian Slope. Canadian Quaternary Association (CANQUA) annual meeting, Halifax, NS, May, 2003.
Mosher, D.C., LaPierre, A.T., and Shylonyk, G. (2004) Theoretical and practical comparisons of 3D seismic and multibeam sonar digital terrain models in deep water on the Scotian Margin. Seabed and Shallow Section Marine Geoscience; Shared Lessons and Technologies from Industry and Academia, Geological Society of London, Petroleum Group Workshop. February 24 – 26, 2004