Collaborative Research: Reconstructing the Origins of the Colorado River: An Integrative Study of the Miocene-Pliocene Bouse Formation

合作研究：重建科罗拉多河的起源：中新世-上新世布斯地层的综合研究

• 批准号: 1545998
• 负责人: Andrew Cohen
• 金额: $ 11.11万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-15 至 2021-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1545998&HistoricalAwards=false
• 关键词: Collaborative; Research; Reconstructing; Origins; Colorado

Despite nearly a century of study, the conditions that controlled initiation of the mighty Colorado River remain poorly understood and vigorously debated. This project seeks to reconstruct the origins of the Colorado River through multidisciplinary study of the Bouse Formation, a complex sedimentary deposit that accumulated in the lower reaches of the valley during river initiation between ~ 6.0 and 4.5 million years ago. The study benefits from collaborations among university professors and students, state and federal agency scientists, a county museum paleontologist, and a local high school teacher. The PI's will use integrated datasets to determine if the Bouse Formation formed in a brackish marine estuary or a large inland lake isolated from the ocean, a key distinction for understanding the origins of the river. This study also explores when and how waters of the Colorado River first reached the sea. Hypotheses will be tested through study of stratigraphic architecture, sedimentology, carbonate geochemistry (including C, O, Sr, and S isotopes), and geochronology. Hypothesis tests emphasize cross-correlation of radiogenic and stable isotope data with major and trace-element chemistry in a precise stratigraphic and structural framework. The PI's will run two workshops: one to engage a broad community of geoscientists, and one to plan a future scientific drilling proposal.

尽管进行了近一个世纪的研究，但控制科罗拉多河发源的条件仍然知之甚少，而且争论也很激烈。该项目旨在通过对鲍斯地层（Bouse Formation）的多学科研究来重建科罗拉多河的起源。鲍斯地层是一种复杂的沉积物，在约 6.0 至 450 万年前的河流萌芽期间积累在山谷下游。这项研究得益于大学教授和学生、州和联邦机构科学家、县博物馆古生物学家和当地高中教师之间的合作。 PI 将使用综合数据集来确定鲍斯组是在咸水河口还是与海洋隔离的大型内陆湖中形成的，这是了解河流起源的一个关键区别。这项研究还探讨了科罗拉多河的水首次流入大海的时间和方式。将通过地层结构、沉积学、碳酸盐地球化学（包括 C、O、Sr 和 S 同位素）和地质年代学的研究来检验假设。假设检验强调放射性和稳定同位素数据与精确地层和结构框架中的主量和痕量元素化学的互相关性。 PI 将举办两场研讨会：一场是为了吸引广泛的地球科学家群体参与，另一场是为了规划未来的科学钻探提案。