Precambrian fluvial rocks of Arctic Canada, and their analogies to modern unvegetated rivers and extra-terrestrial fluvial landscapes

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The Precambrian represents almost 87% of known geological time, yet available information on terrestrial landscapes and surface processes before half a billion year ago depends on a scattered rock record, often exposed in remote locations. Fluvial sedimentology represents a prominent tool to understand the physical and environmental conditions of Precambrian landscapes, and vast regions of Arctic Canada and northern Europe represent the ideal playground to investigate the Precambrian fluvial rock record. Existing models on pre-vegetation rivers assume that virtually all streams were shallow, wide, weakly sinuous, and dominated by flashy runoff. This hypothesis contrasts with the varied geomorphology of modern unvegetated rivers on Earth and ancient fluvial landscapes on Mars. To date, a number of essential questions on Precambrian rivers remain unresolved: were Precambrian rivers comparable to modern unvegetated ones, or to extra-terrestrial fluvial landscapes? Did Precambrian rivers evolve through time in response to changing geodynamic, environmental, and biological forcing? And to what extent did unvegetated rivers differ from modern ones during periods of pan-continental assembly and intense mountain building? Answering these questions requires a worldwide assessment of the Precambrian fluvial rock record, and the extensive remote sensing of unvegetated fluvial landscapes on terrestrial and extra-terrestrial realms with demonstrated hydrologic cycles. This research proposal aims to introduce: a higher level of geological knowledge on under-explored sedimentary basins of Arctic Canada and northern Europe; an innovative database on the geomorphology of fluvial channels on Mars and Titan; a depositional model for modern unvegetated rivers; and finally, a critical comparison between the depositional dynamics of Precambrian, modern-unvegetated, and extra-terrestrial rivers. The research proposal is articulated on 2 field-based projects, and 2 remote-sensing-based projects, and will involve the supervision of several undergraduate and graduate students. Collaboration with federal, territorial, and international geological surveys and several Canadian and European universities is ongoing or in development. The outcomes of this research will prove fundamental for several emerging aspects of modern science, particularly planetary geology and river-resource management.