RPG: An Investigation of U-Pb Systematics in Conodonts

摘要： 氟磷灰石牙形石元素的U-Pb定年研究，为生物地层带与绝对年龄的联系提供了有力的地质工具。 这种组合消除了从零星分布的火成岩的绝对年龄中插值边界年龄的需要。 这种内插是目前绝对地质时标中最大的误差来源之一。 对于为该规划补助金提出的试点研究，PI将确定早二叠世阶段边界的日期，当时阶段边界的命名和地层位置普遍达成一致，PI可以获得丰富的牙形刺。 如果成功的话，PI将提交一份主要提案，将该方法扩展到晚二叠世，当时阶段边界和阶段持续时间受到不断的争论。 晚二叠世地层争议的解决是特别感兴趣的，因为这段时间包括最广泛的中生代生物大灭绝，最低的海平面，基曼反转期的结束，以及许多地球化学参数的快速变化。 该项目的成功将为PI提供一个重要的新工具，以加强她现有的研究，重点是解释海洋生物中保存的同位素变化记录的全球气候变化。

Abstract: The proposed investigation of U-Pb dating of fluor-apatite conodont elements may provide a powerful geologic tool for linking biostratigraphic zones with absolute ages. The combination eliminates the need to interpolate boundary ages from absolute ages derived from sporadically distributed igneous rocks. This interpolation is one of the largest sources of error in current absolute geologic time scales. For the pilot study proposed for this planning grant, the PI will date the stage boundaries in the Early Permian, a time when the nomenclature and stratigraphic positions of stage boundaries are generally agreed upon, and for which the PI can obtain abundant conodonts. If successful, the PI will submit a major proposal to extend the approach into the Late Permian, a time when the stage boundaries and duration of stages are subject to constant debate. Resolution of the Late Permian stratigraphic controversies is of particular interest because the time period includes the most extensive Phanerozoic mass extinction, the lowest sea level stands, the end of the Kiaman Reversed Period, and very rapid apparent rates of change in a number of geochemical parameters. Success of this project will give the PI an important new tool to enhance her existing research, which focuses on the interpretation of global climate change recorded by isotopic variations preserved in marine organisms.