RUI: The Laschamp and Mono Lake Excursions in High Deposition Rate Sediments from Summer Lake, Oregon, USA

RUI：来自美国俄勒冈州萨默湖的高沉积率沉积物中的拉尚和莫诺湖游览

• 批准号: 0911351
• 负责人: Robert Negrini
• 金额: $ 18.34万
• 依托单位: California State University-Bakersfield
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0911351&HistoricalAwards=false
• 关键词: RUI; Laschamp; Mono; Lake; Excursions

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The focus of this project is the recovery of a high-fidelity record of the Earth's magnetic field from ~60,000 to 20,00 years ago. Such records are essential toward a better understanding of the unusually unstable and weak field characterizing this time period. In particular they are necessary to test the proposed geographic distribution, cause, and very existence of two magnetic "excursions" (extreme departures of the magnetic field from its normal state) that likely occurred approximately 41,000 and 34,000 years ago. Because this unusual magnetic field behavior is in principle recorded simultaneously in both marine and nonmarine environments, it can be used as an independent dating method for comparing paleoclimate events from both environments thus leading to confirmation or invalidation of proposed climate connections between the oceans, continents, and atmosphere. Furthermore, because the strength of the magnetic field impacts the production of radiocarbon in the atmosphere, a better understanding of the magnetic field can lead to improved calibrations of radiocarbon dates, the type of corrections that recently resulted in revising our knowledge of interactions between Neanderthals and humans between 40,000 and 30,000 years ago. The research also investigates the usefulness of a lake-level (hence, climate) indicator based on varying magnetic mineral concentration in response to changing lake chemistry with lake depth. The scientific goals of the proposed research are the following: 1) test the hypothesis that the Laschamp and Mono Lake Excursions were separate geomagnetic events that occurred ~40,000 and 34,000 years ago, respectively, 2) constrain the spatial and temporal limits of these records as chronostratigraphic signals and as data for testing geomagnetic field models, and 3) test models of titanomagnetite concentration as an indicator of lake-level change. Several undergraduates and one or two Masters-level graduate students will be substantively engaged in this research. Because CSUB is a teaching university with Hispanic Serving Institution status, both sets of students will be recruited from an ethnically diverse population that is underrepresented in the science disciplines; thus, the project will broaden participation of underrepresented groups in the earth sciences. All of the students will have the opportunity to work at a collaborative, Tier 1 research university for part of their research and/or to present their research at meetings of major scientific societies. The core materials will be rich in paleoclimate indicators thereby fostering future projects for up to a dozen students as part of senior research projects required of all CSUB seniors. Finally, hundreds of general education students and teachers in training will be given updates on this research through lectures and lab exercises by both principal investigators.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目的重点是恢复约60，000至20，000年前地球磁场的高保真记录。这样的记录对于更好地理解这一时期异常不稳定和微弱的磁场是必不可少的。特别是，他们有必要测试两个可能发生在大约41，000年和34，000年前的磁“偏移”（磁场与正常状态的极端偏离）的地理分布，原因和存在。由于这种不寻常的磁场行为原则上同时记录在海洋和非海洋环境中，因此它可以用作比较两种环境中古气候事件的独立定年方法，从而确认或无效海洋，大陆和大气之间的气候联系。此外，由于磁场的强度会影响大气中放射性碳的产生，因此更好地了解磁场可以改善放射性碳年代的校准，这种修正最近导致我们对4万至3万年前尼安德特人和人类之间相互作用的认识。该研究还调查了湖平面（因此，气候）指标的有用性，该指标基于不同的磁性矿物浓度，以响应随湖泊深度变化的湖泊化学。拟议研究的科学目标如下：1）检验Laschamp和Mono Lake Excursions是分别发生在约40，000年和34，000年前的独立地磁事件的假设，2）将这些记录的空间和时间限制作为年代地层信号和测试地磁场模型的数据，3）钛磁铁矿浓度作为湖平面变化指标的测试模型。几个本科生和一个或两个硕士水平的研究生将实质性地从事这项研究。由于Ceclio是一所具有西班牙裔服务机构地位的教学大学，这两组学生将从科学学科代表性不足的种族多元化人口中招募;因此，该项目将扩大代表性不足的群体在地球科学中的参与。所有的学生都将有机会在一个合作的，一级研究型大学工作的一部分，他们的研究和/或在主要科学学会的会议上介绍他们的研究。核心材料将丰富的古气候指标，从而促进未来的项目多达十几名学生的高级研究项目的一部分，要求所有CCED老年人。最后，数百名接受培训的通识教育学生和教师将通过两位主要研究者的讲座和实验室练习获得本研究的最新信息。