The Os Isotopic Record of Himalayan Paleorivers: A New Tool for Understanding Regional Himalayan Tectonic History and Influence on Ocean Chemistry

喜马拉雅古生物的锇同位素记录：了解喜马拉雅区域构造历史及其对海洋化学影响的新工具

• 批准号: 9903278
• 负责人: John Chesley
• 金额: $ 12万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2002-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9903278&HistoricalAwards=false
• 关键词: Os; Isotopic; Record; Himalayan; Paleorivers

9903278John T. Chesley Events in the geologic record responsible for the gradual increase in the 187Os/188Os and 87Sr/86Sr values for seawater through the Tertiary are poorly understood. The rapid growth of radiogenic Os, compared to other isotopic systems, within the crust, offers a new tool, which may help further constrain the large-scale tectonic history of the Himalayan orogen. We will address variations in the Os and Sr and isotopic composition of paleo- Indus, Ganges and Brahmaputra rivers over the last 50 myrs. Our goal is to determine if the Os isotopic composition of paleosols can be related to changes in ocean chemistry and related to the source and timing of foreland basin sediments of major tectonostratigraphic zones of the western and central Nepal.

9903278约翰T.地质记录中的切斯利事件导致了第三纪海水中187 Os/188 Os和87 Sr/86 Sr值的逐渐增加，但人们对此知之甚少。放射成因的Os的快速增长，相比其他同位素系统，在地壳内，提供了一个新的工具，这可能有助于进一步限制喜马拉雅造山带的大规模构造历史。我们将讨论在过去的50万年的古印度河，恒河和雅鲁藏布江的Os和Sr和同位素组成的变化。我们的目标是确定古土壤的Os同位素组成是否与海洋化学变化有关，并与尼泊尔西部和中部主要构造地层区的前陆盆地沉积物的来源和时间有关。