Understanding Jurassic and Cretaceous High Arctic Paleoenvironmental and Paleoclimate Change

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Understanding the paleoenvironmental and paleoclimatic evolution of Canada’s Arctic region, as a crucial component of Earth’s climate system, is fundamental to assess short- and long-term climate, environmental, and paleogeographic changes during Jurassic and Cretaceous time. Our 2011 and 2014 Arctic field seasons were tremendously successful; we documented for the first time major Cretaceous paleoceanographic and paleoclimatic events (e.g. Oceanic Anoxic Events (OAEs), late Aptian cold snap) in a 3.5 km-thick sedimentary succession of the Canadian High Arctic Sverdrup Basin. Our results indicate the great potential and feasibility to describe, sample and study outcropping stratigraphic sections to decipher on short- and long-term timescales marine paleoenvironmental and paleoclimate events and dynamics during critical times of the Cretaceous. This project proposes to assess the impact of enhanced organic carbon burial in the Cretaceous High Arctic Sverdrup Basin on global climate perturbations of the carbon cycle such as the Toarcian OAE, the early Aptian OAE 1a and the late Cenomanian OAE 2 as case studies. We intent to evaluate the dynamics of carbon burial and their associated paleoceanographic and paleoclimate consequences. Our previous investigation seems to suggest that the Cretaceous High Arctic Ocean plays an important role as carbon sink of global significance. We propose to test this hypothesis and quantify the global impact of carbon burial in the Cretaceous High Arctic Ocean. In addition, our international research team will extent the focus on Jurassic to early Cretaceous long-term climate development over a period of approximately 60 m.y. (Savik, Awingak, Deer Bay to lower Isachsen formations and late Cretaceous Kanguk Formation) and calibrate the developing record of Arctic diatom and silicoflagellate evolution within a chronostratigraphic framework of the late Cretaceous. The latter will illuminate a long-standing dark interval in the early record of diatom evolution between the exceptionally well-preserved middle Albian diatoms from the Weddell Sea of Antarctica and the well documented Campanian/Maastrichtian diatom rich deposits.