SWEAT, AUSWUS, AUSMEX, or Other? Testing Proterozoic Supercontinent Reconstructions by Refining 1.8-1.6 Ga Apparent Polar Wander Paths from Laurentia and Australia

SWEAT、AUSWUS、AUSMEX 还是其他？

• 批准号: 0310922
• 负责人: David Evans
• 金额: $ 20.3万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2006-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0310922&HistoricalAwards=false
• 关键词: SWEAT; AUSWUS; AUSMEX; Other; Testing

Tectonostratigraphic syntheses of Proterozoic rocks worldwide have allowed plausible reconstructions for Rodinia, the early Neoproterozoic supercontinent, and its predecessor Nuna, assembled by 1.8 Ga. Many different reconstructions have been postulated, however, that have yet to be tested with high-quality paleomagnetic data. Tectonostratigraphic similarities between Archean-Proterozoic terrains in Laurentia (cratonic North America) and Australia form the bases for most modern conceptions of Rodinia; if valid, these comparisons would also pertain to Nuna configurations. One recent high-quality paleomagnetic study has cast doubt upon the most popular earlier juxtapositions of Proterozoic Laurentia and Australia, known as SWEAT and AUSWUS; that study identified a third possible reconstruction, dubbed AUSMEX. The PI seeks to test these hypothesized juxtapositions further, by collecting new paleomagnetic and geochronological data from well preserved 1.8-1.6 Ga volcanic- sedimentary successions in central Canada and northern Australia. These results will generate refined apparent-polar-wander paths for the two cratons during that interval and thus permit quantitative tests for Nuna and Rodinia reconstructions. Broader scientific impacts of the proposed research follow the recognition that accurate continental reconstructions form paleogeographic foundations for all aspects of Earth surface processes, and they provide boundary conditions for models of mantle geodynamics. Broader impacts also include research training for graduate and undergraduate students, including a female graduate student aspiring toward a career in academia.

全球元古代岩石的构造地层合成允许合理的重建Rodinia，早期新元古代超大陆，及其前身努纳，组装1.8 Ga。然而，许多不同的重建已经被假定，还有待高质量的古地磁数据进行测试。在劳伦蒂亚（北美洲）和澳大利亚的太古代-元古代地体之间的构造地层相似性构成了大多数现代Rodinia概念的基础;如果有效的话，这些比较也适用于Nuna配置。最近的一项高质量的古地磁研究对元古代劳伦和澳大利亚最受欢迎的早期并列提出了质疑，称为SWEAT和AUSWUS;该研究确定了第三种可能的重建，称为AUSMEX。PI试图通过从加拿大中部和澳大利亚北方保存完好的1.8-1.6 Ga火山-沉积序列中收集新的古地磁和地质年代学数据，进一步测试这些假设的并置。这些结果将产生精细的视极漂移路径的两个Ephonons在该时间间隔，从而允许定量测试努纳和Rodinia重建。拟议研究的更广泛的科学影响是认识到精确的大陆重建形成了地球表面过程各个方面的古地理基础，并为地幔地球动力学模型提供了边界条件。 更广泛的影响还包括对研究生和本科生的研究培训，包括一名渴望在学术界工作的女研究生。