Tidal deposits in time and space

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The gravitational attraction of the Moon and Sun on the world ocean creates tides. Even in areas with a small tidal range, the water motions associated with the tidal rise and fall of water level play an important role in sediment transportation and deposition. Tide-dominated sedimentation occurs along about one third of the world's marine coastline, in areas with a large tidal range and/or where wave energy is low. Even in wave-dominated situations, however, tidal currents dominate sedimentation in channel networks behind barrier islands, extending long distances inland from the coast through a fluvial-marine transition zone. The work proposed here is directed toward providing an improved understanding of two particular tidal sub-environments: 1) the tidal-fluvial transition zone that can be 10s to 100s of kilometres long; and 2) the mouth-bar and delta-front region of tide-dominated deltas. The proposed research integrates studies in modern tidal-channel systems with outcrop studies of comparable ancient examples. The results of these studies will also be used as a basis for experimental work that explores the factors that control the shape in plan of tidal meanders as a function of location through the fluvial-marine transition. Industrial support is also being sought to undertake several additional projects that would complement the work proposed here. The objectives of the research are to improve our knowledge of sediment dynamics in these two sub-environments, and to develop criteria by which tidal deposits can be interpreted more precisely than has been the case in the past. The research will have application the management of modern coastal systems, but the primary application is in the petroleum industry where it will improve the ability to predict the three-dimensional geometry of reservoir units and the mudstone layers that act as baffles and barriers to the flow of oil and natural gas. There will be direct application to the development of the oil reserves hosted in the subsurface portion of the McMurray Oil Sands.