Understanding Jurassic and Cretaceous High Arctic Paleoenvironmental and Paleoclimate Change

了解加拿大北极地区的古环境和古气候演变，作为地球气候系统的重要组成部分，是评估侏罗纪和白垩纪时期短期和长期气候，环境和古地理变化的基础。我们的2011年和2014年北极领域的季节是非常成功的;我们第一次记录了主要的白垩纪古海洋和古气候事件（例如海洋浮游生物事件（OAE），Aptian寒流）在加拿大高北极Sverdrup盆地的3.5公里厚的沉积序列。我们的研究结果表明，描述，采样和研究露头地层剖面的巨大潜力和可行性，在白垩纪的关键时期，在短期和长期的时间尺度上破译海洋古环境和古气候事件和动力学。该项目拟评估白垩纪高北极Sverdrup盆地有机碳埋藏增强对碳循环全球气候扰动的影响，如Toarcian OAE，早期Aptian OAE 1a和晚期Cenomanian OAE 2作为案例研究。我们的目的是评估碳埋藏的动力学及其相关的古海洋学和古气候后果。白垩纪高冰期北冰洋是一个具有全球意义的碳汇。我们建议测试这一假设，并量化在白垩纪高北冰洋碳埋藏的全球影响。此外，我们的国际研究团队将扩大对侏罗纪到早白垩世长期气候发展的关注，时间约为6000万年。（Savik、Awingak、Deer Bay至Isachsen组下部和晚白垩世Kanguk组），并在晚白垩世年代地层格架内标定了北极硅藻和硅鞭藻演化的发育记录。后者将照亮一个长期存在的黑暗间隔，在硅藻进化的早期记录异常完好的中Albian硅藻从南极洲威德尔海和有据可查的坎帕尼亚/马斯特里赫特硅藻丰富的存款。

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.