Reconstruction of the Water Column Structure of Jurassic and Cretaceous Epeiric Seas: Biomarkers and their Carbon Isotopic Composition

侏罗纪和白垩纪表海水柱结构的重建：生物标志物及其碳同位素组成

• 批准号: 9614769
• 负责人: Fabien Kenig
• 金额: $ 17.12万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-02-01 至 2001-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9614769&HistoricalAwards=false
• 关键词: Reconstruction; Water; Column; Structure; Jurassic

9614769 Kenig The goal of the proposal is to reconstruct the water-column structure of a Jurassic and a Cretaceous epeiric sea using biomarkers and their isotopic composition. More specifically, our efforts will concentrate on the reconstruction of the water-column chemistry, and its evolution during the deposition of two sediment formations, the Oxford Clay (Middle Callovian, UK and the Greenhorn Formation (Western Interior Seaway, Cenomano-Turonian, USA). We will use this information to understand paleo-oceanographic conditions at the onset of water column stratification, biofacies distribution, and organic matter accumulation in epeiric seas. These results will be used to test the relationship between biofacies and benthic oxygen level. These results will be used to further constrain existing paleo-oceanographic circulation models. The first objective is to determine the geographic extent of intermittent anoxic events that characterized the accumulation of the organic mater-rich fossil-laggerstatten of the Lower Oxford Clay. To achieve this, Middle Callovian sediments with well defined biofacies from Scotland, Central and Southern England, France, Germany, Switzerland and Poland will be analyzed for their free, sulphur-bound, and ether-bound hydrocarbon biomarkers. The second objective is to use the molecular fossil record of thermally immature samples from the Greenhorn formation to reconstruct the water-column structure of the Western Interior Seaway during the Cenomanian and Turonian. Three sections will be investigated in detail for their free, sulphur-bound, and ether-bound molecular fossils. This analytical procedure will allow us to target the molecules that are diagnostic for the water-column structure. It will result in the development of an efficient analytical scheme allowing analysis of the vast number of samples necessary for precise constraint of the water-column structure and chemistry of a large geographical area. The third objective will be to geographicall y extend the water-column reconstruction of the Western Interior Seaway during the Cenomanian and Turonian. We will use these results to constrain the computer models of paleo-oceanographic circulation constructed for the Western Interior Seaway. Comparison of the results obtained from the Middle-Callovian of Western Europe will enhance our understanding of paleo-oceanographic circulation in epeiric seas. Based on literature data and our water-column reconstruction, a model of the paleo-oceanographic circulation for the Middle Callovian of Western Europe will be proposed.

小行星9614769 该提案的目标是利用生物标志物及其同位素组成重建侏罗纪和白垩纪陆表海的水柱结构。 更具体地说，我们的努力将集中在重建的水柱化学，其演变过程中的沉积物形成，牛津粘土（中卡洛夫，英国和Greenhorn形成（西部内陆航道，Cenomano-Turonian，美国）。 我们将利用这些信息来了解古海洋条件的水柱分层，生物相分布，并在陆表海有机质积累的发病。 这些结果将被用来测试生物相和底栖氧水平之间的关系。 这些结果将被用来进一步约束现有的古海洋环流模型。 第一个目标是确定间歇性缺氧事件的地理范围，其特征是下牛津粘土富含有机质的化石laggerstatten的积累。 为了实现这一目标，将分析苏格兰、英格兰中部和南部、法国、德国、瑞士和波兰的具有明确生物相的中卡洛夫沉积物的游离、硫结合和醚结合烃生物标志物。 第二个目标是利用分子化石记录的热不成熟的样品从Greenhorn形成重建水柱结构的西部内陆海道在森诺曼和Turonian。 三个部分将详细研究其自由，硫结合，醚结合分子化石。 这种分析方法将使我们能够瞄准那些能够诊断水柱结构的分子。 这将导致制定一个有效的分析计划，以便分析大量必要的样本，从而精确限制一个大地理区域的水柱结构和化学性质。 第三个目标是在塞诺曼和图伦期间在地理上扩大西部内陆航道的水柱重建。 我们将使用这些结果来约束为西部内陆海道建造的古海洋环流的计算机模型。 通过对西欧中-卡洛阶的研究结果进行比较，将有助于加深对陆表海古海洋环流的认识。 根据文献资料和我们的水柱重建，提出一个模式的古海洋环流西欧中卡洛夫。