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The morphology of turbidite slope channels and the distribution of reservoir and nonreservoir facies within them are commonly complicated by the interaction of the channels with the development of structurally induced topography. The pattern of channel response may be dictated by the timing of structural growth related to channel development, the size and shape of the structures, the orientation of the structure to depositional dip, and the erosional power of the channels.
Several three-dimensional seismic data sets have been examined from passive margins deformed by gravity-driven tectonics to investigate the range of responses that large, third-order erosional channel complex systems can show to slope topography. The examples are examined with respect to timing of the growth-related seabed topography versus timing of channel formation and the erosive power of the flows within the channel.
Structures that develop aerially limited sea-floor topography, which predates channel development, cause turbidite channels to take a moderate diversion as they traverse the slope. Where similar structures are more laterally extensive, channels may take extreme diversions, commonly kilometers along slope before continuing down the regional slope.
When the erosion of the flows is strong enough and can overcome the rate of growth of the structure, channels can continue to incise across the growing structure. If the rate of growth of the structure is higher, the channel systems shift systematically sideways to avoid the rising topography. The style of the sedimentation-topography interaction has a strong but commonly subtle effect on the geometry, internal stratigraphic architecture, and nature and distribution of the facies deposited within and around the channels.
Mike Mayall has a B.Sc. degree from Cardiff University and an M.Sc. degree and Ph.D. in sedimentology from the University of Reading. He joined BP in 1980 and is currently a senior advisor in sedimentology for BP. He has worked in many parts of the world.
Lidia Lonergan is a reader in geotectonics at Imperial College, London. She has a Ph.D. from Oxford University. She has previously worked at Shell Research in the Netherlands, held a Royal Society University Research Fellowship, and was recently a research fellow at BP Exploration. Her current main research focus is the interaction of deformation and sedimentation in deep-water settings.
Andrew Bowman has a B.Sc. degree from the University of Leeds, an M.Sc. degree from the University of London, and a Ph.D. from Imperial College, London. He has worked as a geologist for BP since 2003 on projects in Azerbaijan and Angola. He currently works for BP Egypt.
Stephen James is currently the well planning and execution team leader for BP's Angola Business Unit PSVM (Plutao, Saturno, Venus, and Marte fields) Project. He holds a B.Sc. degree in geology from University College, London, and a Ph.D. in sedimentology from the University of Aston, Birmingham. He has worked on a variety of reservoir management and development projects in Angola, Kuwait, the Netherlands, and Nigeria.
Keith Mills has more than 35 years of experience as a geophysicist, initially in seismic processing then as an employee for BP, and he now works for BP as a consultant. He has held a variety of posts in the United Kingdom, Norway, United States, China, and Kuwait. He is currently working on the BP Middle East team. Keith has a B.Sc. degree in geology from the University of Leicester.
Tim Primmer has a B.Sc. degree and Ph.D. from the University of Bristol. He joined BP in 1985 and has spent the last 7 years leading subsurface teams developing deep-water turbidite reservoirs in the United Kingdom and Angola.
Dave Pope has 17 years of industry experience, primarily working as a seismic interpreter, and 9 years of experience working in deep-water Angola turbidite reservoirs. He is currently leading a subsurface team developing deep-water turbidite reservoirs offshore Angola.
Louise Rogers has an M.Geol. degree from the University of Leeds and is currently working toward an M.Sc. degree in petroleum engineering from Heriot-Watt University. She has worked as a geologist for BP since 2006 on projects in Azerbaijan and Angola and currently works for BP North Africa.
Roxanne Skeen is a Colorado School of Mines geophysics graduate who has previously worked with IBM in Houston and the Petroleum Company of Trinidad and Tobago. In her 11 years at BP, she has been a development geophysicist with BP Trinidad, interpreting 3-D seismic data and doing integrated well planning in shallow-marine environments and also with BP Angola working on deep-water environments.