Ostracode-Shell Luminescence Dating for Quaternary Deposits

第四纪沉积物介壳壳发光测年

• 批准号: 0087827
• 负责人: Glenn Berger
• 金额: $ 14.05万
• 依托单位: Nevada System of Higher Education, Desert Research Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0087827&HistoricalAwards=false
• 关键词: Ostracode; Shell; Luminescence; Dating; Quaternary

ABSTRACTOSTRACODE-SHELL LUMINESCENCE DATING FOR QUATERNARY DEPOSITSThis proposal intends to build on preliminary feasibility tests, to develop a new luminescence clock for the direct dating of an important Quatemary paleoenvironmental proxy indicator: ostracode shells. Non-marine ostracode shells serve as proxy indicators of paleoenvironmental conditions in lakes, ponds, springs and streams. Presently these shells can be dated directly by radiocarbon methods, but a means to date them directly when older than 35-40 ka would provide opportunities for new discoveries in the worldwide effort to reconstruct details of paleoenvironmental histories from continental sedimentary records.Preliminary work by the PI indicates that ostracode shells have some desired luminescence properties. However, refined sample preparation protocols suitable for luminescence dating need to be developed, and almost nothing is known of their likely useful age range. Natural samples of ostracode shells will be collected from independently well-dated (by 14C) lacustrine beds (late Pleistocene age) from the lake Bonneville Basin (northwestern Utah) and from Mono Lake (eastem Califomia). The foundations for reliable luminescence dating protocols will be established. These protocols will then be applied to one or two samples older than ca. I00 ka, to extrapolate from the developmental tests. This research will form the basis of a graduate student's thesis project.

第四纪沉积物的壳层发光测年他的提议旨在初步可行性试验的基础上，开发一种新的发光时钟，用于直接测定一种重要的第四纪古环境指标：介形虫贝壳。非海洋介形类贝壳是湖泊、池塘、泉水和溪流中古环境条件的替代指标。目前，这些壳体可以直接用放射性碳法测年，但在35-40ka以前直接测年的方法将为从大陆沉积记录重建古环境历史细节的世界范围内的新发现提供机会。PI的初步工作表明，介形虫壳体具有一些所需的发光特性。然而，适合于发光测年的改进的样品制备方法还需要开发，而且几乎不知道它们可能有用的年龄范围。介形类贝壳的自然样本将从独立测年(14C)的湖泊层(更新世晚期)和Mono湖(东部Califomia)收集。这将为可靠的发光测年方案奠定基础。然后，这些协议将应用于一个或两个早于约100ka的样品，以从发育测试中推断出来。这项研究将构成研究生论文项目的基础。