Source to Sink Systems in the Cretaceous Western Interior of North America

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The proposed research is part of my long-term research program on Cretaceous source-to-sink basin analysis, incorporating high-resolution sequence stratigraphy, with an even broader goal of linking our stratigraphic analysis of sea level changes to emerging global astrochronological cycle charts. My group is also focused on reservoir characterization of sandstone elements within studied units, with application to the hydrocarbon industry.  Our primary focus is on Cretaceous "greenhouse" sedimentary sequences in the Western Interior Seaway of North America. Detailed field and subsurface studies are designed to answer questions about the larger-scale stratigraphic controls on sedimentary basin fills (e.g. eustasy versus tectonics), and equally important questions relating to the formative processes of smaller-scale sedimentary units, with a specific focus on paleodischarge estimates based on analysis of river deposits. High-resolution outcrop and subsurface stratigraphic analysis, integrated with chronometric and biostratigraphic control, enable the elucidation of the nature and degree of cyclicity in a global "Greenhouse". There is evidence of climate-driven Milankovitch-scale cyclicity, suggesting that the Cretaceous was not an ice-free time, as has been hypothesized by some. Documentation of the climate and sea-level in a greenhouse period can be used to predict future greenhouse scenarios, such as may result from the anthropogenically-induced climate change that is of present societal concern. The research is also focused on using information from the depositional system (especially provenance and paleodischarge studies of the fossilized trunk rivers) to make inferences about paleo-drainage basin size and relief, connectivity of drainage systems within mountain belts, paleoclimate, and plate-tectonic reconstructions. Petrographic analysis combined with age-dating of detrital zircons is used to evaluate provenance and drainage area, as well as tectonic controls on sedimentation. Age-dating of detrital zircons can also help establish the chronology of river deposits, especially when used in conjunction with age dates from bentonites integrated with biostratigraphic control. We are also incorporating newer technologies, and particularly the use of Unmanned Aerial Vehicles (UAV's or "drones") integrated with GPS/GIS to capture 3D virtual outcrops. These datasets include plan-view images of Cretaceous channel belts, as well as cliff-faces of a variety of fluvial and shallow marine facies. These digital datasets allow for detailed facies architectural analysis of otherwise inaccessible sections. In addition to the scientific and societal relevance, our research is directly applicable to the Canadian energy resources sector.