Deciphering Lithospheric and Deeper Mantle Contributions to the Surface History of the North American Arctic From the Unique Mantle to Surface Record of Kimberlites

从独特的地幔到金伯利岩的地表记录，解读岩石圈和更深地幔对北美北极地表历史的贡献

• 批准号: 1844182
• 负责人: Rebecca Flowers
• 金额: $ 38.88万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1844182&HistoricalAwards=false
• 关键词: Deciphering; Lithospheric; Deeper; Mantle; Contributions

Fundamental questions exist about the deep-time surface history of vast continental interior regions. In Arctic North America, diamondiferous kimberlite magmas of diverse age that bear fragments of rock entrained from deep in the Earth erupted through continental blocks of contrasting age, structure, and history. The disparate relationships provide the opportunity to evaluate the deep and shallow evolution across the region to illuminate how the histories at different depths are linked. This project will develop new and reinforce existing cross-disciplinary research relationships among U.S. and Canadian scientists studying processes at different depths in the Earth, train a CU-Boulder PhD student, and foster diversity through support of an underrepresented minority summer intern. A workshop will gather the project team and other members of the geologic, petrologic, and geodynamic communities to improve ties among these groups and enhance understanding of how deep Earth through surface processes are connected. This project's goals are to decipher the Phanerozoic surface history across the North American Arctic, identify relationships with the architecture and history of the lithospheric mantle, evaluate connections with the history of kimberlite magmatism, and consider the role of sublithospheric processes in these records. This will be accomplished by exploiting the unique mantle to surface record preserved within Arctic kimberlite pipes. Specifically, this project will (1) decipher the Arctic surface history and its spatial variability by integrating AHe data for kimberlite and basement samples with geologic constraints on the surface evolution borne by the pipes, (2) compare this surface record with the composition and evolution of the underlying mantle roots, which are being mapped by the project's University of Alberta collaborators through intensive study of these same kimberlites and their mantle xenolith suites, and (3) use a 3D-dynamic model of thermochemical convection to predict the Phanerozoic thermal evolution of the upper asthenosphere below North America. This project is jointly supported by the Petrology & Geochemistry, Geophysics, and Tectonics programs in the Division of Earth Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

关于广阔的大陆室内地区的深层表面历史存在基本问题。在北极北美，多种年龄的钻石金伯利特岩浆，这些岩石带有从地球深处覆盖的岩石碎片，穿过对比的年龄，结构和历史的大陆块。不同的关系为评估整个地区的深层进化提供了机会，以阐明不同深度的历史如何相连。该项目将开发新的，并加强美国和加拿大科学家之间现有的跨学科研究关系，研究地球上不同深度的过程，培训Cu-Boulder博士学位学生，并通过支持代表性不足的少数民族暑期实习生来促进多样性。研讨会将聚集项目团队和地质，岩石学和地球动力学群落的其他成员，以改善这些群体之间的联系，并增强对地面过程如何连接地球的了解。该项目的目标是破译北美北极的植物学表面历史，确定与岩石圈地幔的建筑和历史的关系，评估与金伯利特岩浆岩的历史，并考虑sublithospheric过程在这些记录中的作用。这将通过利用独特的地幔以保存在北极金伯利岩管中的表面记录来实现。具体而言，该项目将（1）通过将金伯利特和地下样品的AHE数据整合到对管道表面进化的地面进化中的AHE数据来解释北极的表面历史及其空间可变性，（2）将其与底层地下的斗篷的组成和进化相提并论，这些记录与底层的kim依次是由Alberta绘制的Alberta and alberta unberta unberta unberta and alberta and the Incortistor and the Intivors eysore extorel and olberty extornor extore eysore eysore eysore elestor。地幔异种石套件和（3）使用热化学对流的3D动力模型来预测北美以下小动摇圈的植物学热演化。该项目得到了地球科学部的岩石学和地球化学，地球物理和构造计划的共同支持。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准通过评估来支持的。