Processes and products of deep-sea sediment-routing systems from bed- to basin-scale

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Holistic interpretations of deep-sea paleo-environments from the sedimentary rock record are critical for deducing significant events in the Earth's past, such as triggering of major submarine avalanches, uplift and erosion of mountain belts, and climate-driven variations in sea-level. Moreover, these interpretations provide a predictive framework for the distribution of vast hydrocarbon and water resources, which are widely hosted in rocks of deep-sea origin on the continental margins of Canada, and beyond. The deep oceans have proved to be particularly difficult to study due to their inaccessibility and prevalence of destructive events, such as turbidity currents. Limited observations of deep-sea environments makes interpretations of their deposits in the geological record particularly challenging. In this research program, the record of long-term sediment-delivery through deep-sea channel systems is used to develop and apply novel models that: (1) establish recognition of deposits formed by deep-water sediment transport processes; and (2) use the sedimentary archive of submarine fan-channel systems to deduce long-term variations in sediment supply to sedimentary basins, the generation and destruction of accommodation space for sediment to accumulate, and changes in sediment source areas related to tectonics or climatic fluctuations. Deep-sea deposits provide critical archives of these processes at the ends of continent-draining sediment-routing systems. Exposures of the Cretaceous Nanaimo Group on the Gulf Islands of British Columbia are established as a world-class natural laboratory for the study of deep-sea sedimentary deposits, and are the foundation for the proposed research program. The research program will result in training of 14 highly qualified personnel, including 5 BSc, 4 MSc and 4 PhD students, as well as 1 postdoctoral scholar, each of which will be well positioned to gain employment in industry, academia, or government upon graduation. HQP will use traditional and innovative field methods and laboratory techniques in order to constrain the characteristics and distribution patterns of deep-sea rock units, deduce internal and external controls on formative sedimentary processes, and estimate depositional rates at various scales of investigation. This knowledge is essential for enhanced predictions of the distribution and quality of hydrocarbon-bearing deep-water rocks on continental margins, with significant potential long-term economic implications related to the identification and development of energy resources in eastern Canada. Furthermore, characterization of aquifers hosted in turbiditic bedrock of the Gulf Islands study area will inform better drinking water management strategies for a significant population of British Columbia.