Collaborative Research: Paleoenvironment and Paleoecology of a Late Cretaceous, High-Latitude Locality on Devon Island, Nunavut, Canada

合作研究：加拿大努勒维特德文岛晚白垩世高纬度地区的古环境和古生态

• 批准号: 0241002
• 负责人: Karen Chin
• 金额: $ 23.57万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0241002&HistoricalAwards=false
• 关键词: Collaborative; Research; Paleoenvironment; Paleoecology; Late

This is a collaborative proposal by Principal Investigators at the Universities of Colorado and New Mexico. They will document the stratigraphy, paleontology, geochemistry and geochronology of Late Cretaceous sediments in the Eidsbotn and Viks Fiord grabens, on Devon Island in the Canadian High Arctic. Devon Island was selected because a preliminary survey of the Eidsbotn graben in 1998 demonstrated that it holds an unusually diverse assemblage of marine organisms and coprolitic trace fossils. This fossil assemblage represents a complex ecosystem that was characterized by an apparently temperate Arctic environment, even though it was subject to extreme photoperiodic seasonality. A study of this unique site will provide the geological framework that will help reconstruct the paleoenvironment of this high-latitude locality and substantially increase our understanding of Late Cretaceous Arctic marine ecosystems. Reconnaissance sampling of the Eidsbotn area revealed a wide variety of fossils, both whole and fragments, and a high concentration of unusual green and cream-colored coprolites. A systematic sampling of the Late Cretaceous paleontological resources will provide stratigraphic and facies context, contribute more material for taxonomic identification, indicate patterns of abundance, and almost certainly reveal new Arctic taxa. The sediments are reported to contain numerous bentonites, glauconitic sands, siltstones, and mudstones that are overlain by a peat of an unknown age. Stratigraphic sections will be measured, described and sampled for biofacies and geochemical analyses. Fossils will be collected and taphonomic conditions described. Bentonite samples will be collected for geochronological analysis of mica, sanidine, and zircon, and palynological samples will refine the lithostratigraphy and elucidate the age of the peat that overlies the Eidsbotn section. Petrographic and geochemical analyses of coprolites will provide evidence of trophic interactions, and faunal lists will indicate the structure and ecological niches in the paleoecosystem. Oxygen isotopic analysis of the phosphate will contribute proxy sea-surface temperature information and may provide evidence for water-column temperature gradients, paleosalinity, and sedimentation rates. The suite of sedimentary and paleontological resources in the Eidsbotn and Viks Fiords will provide a unique opportunity to fully characterize the paleoenvironment and paleoecology of a Late Cretaceous high-latitude marine locality, and to test paleoclimatic models for that period. This project will also engage undergraduates, graduate students, people from the Inuit community, and international and intercultural discourse.

这是由科罗拉多大学和新墨西哥州大学的主要研究人员合作提出的一项建议。 他们将记录加拿大北极高纬度地区德文郡岛上的Eidsbotn和Viks峡湾地堑中晚白垩世沉积物的地层学、古生物学、地球化学和地质年代学。之所以选择德文郡岛，是因为1998年对艾兹博顿地堑的初步调查表明，该岛拥有异常多样的海洋生物和粪化石遗迹。 这个化石组合代表了一个复杂的生态系统，其特征是明显温和的北极环境，尽管它受到极端光周期季节性的影响。 对这一独特地点的研究将提供地质框架，有助于重建这一高纬度地区的古环境，并大大增加我们对晚白垩世北极海洋生态系统的了解。 对Eidsbotn地区的勘察取样显示，化石种类繁多，既有完整的，也有碎片，还有高浓度的不寻常的绿色和奶油色粪化石。 晚白垩世古生物资源的系统采样将提供地层和岩相背景，为分类鉴定提供更多材料，表明丰度模式，几乎可以肯定地揭示新的北极分类群。据报道，沉积物中含有大量的碳酸盐岩、碳酸盐砂、粉砂岩和泥岩，上面覆盖着年龄未知的泥炭。 将对地层剖面进行测量、描述和取样，以进行生物相和地球化学分析。 将收集化石并描述埋藏条件。 将收集膨润土样品进行云母、透长石和锆石的地质年代学分析，孢粉学样品将细化岩石地层学，并阐明覆盖在Eidsbotn剖面上的泥炭的年龄。 粪化石的岩相学和地球化学分析将提供营养相互作用的证据，动物群列表将表明古生态系统的结构和生态位。磷酸盐的氧同位素分析将有助于代理海表面温度信息，并可能提供水柱温度梯度，古盐度和沉积速率的证据。 在Eidsbotn和维克斯峡湾的沉积和古生物资源套件将提供一个独特的机会，充分表征晚白垩世高纬度海洋地区的古环境和古生态，并测试该时期的古气候模型。 该项目还将吸引本科生、研究生、因纽特人社区的人以及国际和跨文化对话。