ROW: Rb-Sr and Stable Isotope Investigations of the Front Range Migmatites

ROW：前岭混合岩的铷-锶和稳定同位素研究

• 批准号: 8810011
• 负责人: Sakiko Olsen
• 金额: $ 4.79万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-12-01 至 1990-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8810011&HistoricalAwards=false
• 关键词: ROW; Rb; Sr; Stable; Isotope

The purpose of this ROW grant is to carry out Rb/Sr and stable isotopic analyses of migmatites from the Colorado front range to understand isotopic mobility during partial melting of crustal rocks. Preliminary Rb/Sr isotope analysis of leucosomes and adjacent selvages and paleosomes of these rocks have indicated that the leucosome size is a factor in the extent of isotope migration and resetting of the Rb/Sr age, however considerable ambiguity exists about other factors including fluid interactions that may affect the mobility and effective volume of homogenization of the Rb/Sr systems. This study will focus on an outcrop having widely variable sizes of leucosomes. Results may help understand the geologic meaning of Rb/Sr data, now considerably out of favor as an age dating tool.

这项ROW资助的目的是对科罗拉多锋面混辉岩进行Rb/Sr和稳定同位素分析，以了解地壳岩石部分熔融过程中的同位素流动性。初步分析了这些岩石的白色体及其邻近的边缘和古体的Rb/Sr同位素，表明白色体的大小是影响同位素迁移程度和Rb/Sr年龄重置的一个因素。然而，包括流体相互作用在内的其他因素可能影响Rb/Sr体系的迁移率和均质化有效体积，这方面存在相当大的模糊性。这项研究将集中在一个白体大小变化很大的露头上。结果可能有助于理解Rb/Sr数据的地质意义，而Rb/Sr数据现在已不再被用作年龄测年工具。