Quaternary Paleohydrology of the Western Great Basin Province, USA: The Radiogenic Isotope Record of Lacustrine Sediments of the Owens River System

美国西部大盆地省第四纪古水文学：欧文斯河系统湖泊沉积物的放射性同位素记录

• 批准号: 9814943
• 负责人: Brian Stewart
• 金额: $ 14.26万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-15 至 2001-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9814943&HistoricalAwards=false
• 关键词: Quaternary; Paleohydrology; Western; Great; Basin

9814943StewartThis award supports a radiogenic isotope study of a unique continental record of weathering and climate change preserved in a series of playa lakes in the southeastern California section of the Great Basin. This chain of periodically interconnected lakes, referred to as the Owens River System, is the repository for essentially all of the clastic and chemical sediments shed over the past several million years from the eastern Sierra Nevada from just south of Mono Lake to the Garlock Fault. Despite the large amount of work that has been carried out on the Owens Rivers System, there have been relatively few studies examining the sources of cations and clastic sediments in these Great Basin lacustrine basins. Strontium (Sr) and neodymium (Nd) isotopes are potentially sensitive tracers of cation inputs, both in the dissolved form and as suspended sediments. Preliminary data suggest that these isotope tracers can be successfully used in the Owens River System to monitor (1) changes in location of chemical weathering and sediment sources (therefore of precipitation patterns); (2) the relationship of chemical to mechanical weathering in the alpine environment; and (3) hydrologic connectivity between lakes that share a common water supply during wet periods but that become closed, isolated basins during dry periods. Integration of the results from the proposed study with previous and ongoing work in the Owens River System will provide powerful constraints on Quaternary climate shifts in the Basin and Range Province, which have in turn been linked to North Atlantic and global climate fluctuations.

9814943STEWARTTHIS奖支持一项放射性同位素研究，该研究对伟大盆地东南部一系列普拉亚湖中保存的风化和气候变化的独特记录。 这条定期相互联系的湖泊被称为欧文斯河系统，是过去几百万年内从单声道湖南部到Garlock断层的几百万年中所有碎屑和化学沉积物的存储库。 尽管在欧文斯河系统上进行了大量工作，但在这些伟大的盆地湖泊中，很少有研究研究阳离子和碎屑沉积物的来源。 在溶解形式和作为悬浮的沉积物中，锶（SR）和霓虹灯（ND）同位素都是阳离子输入的潜在敏感示踪剂。 初步数据表明，这些同位素示踪剂可以在欧文斯河系统中成功使用，以监测（1）化学风化和沉积物来源的位置变化（因此降水模式）； （2）在高山环境中化学与机械风化的关系； （3）在潮湿时期共享共同供水但在干旱期间隔离的盆地的湖泊之间的水文连通性。 拟议研究的结果与欧文斯河系统的先前和正在进行的工作的结果整合将对盆地和山脉省的第四纪气候变化产生强大的限制，而这又与北大西洋和全球气候波动有关。