EAR-PF:Constraining the burial and unroofing history of the Rae craton, Baffin Island, from multiple low temperature thermochronometers and secondary Fe-oxide (U-Th)/He dating

Alexis K.奥尔特已被授予NSF地球科学博士后奖学金，在亚利桑那大学开展研究和教育计划。本研究调查的地表响应的火山岩近场板块边界活动，包括变形，从高地形，前陆盆地的发展，弯曲隆起，和折返相关的流体循环地区的沉积。拟议的研究重点是Rae克拉通，暴露在巴芬岛，加拿大，一个独特的板块边界附近的地方，在整个中生代，并旨在约束的规模和模式的板块埋藏和去顶与一套热计时器，包括磷灰石（U-Th）/He，磷灰石裂变径迹，锆石（U-Th）/He定年。流体流动和次生矿化与岩石折返，将通过赤铁矿（U-Th）/He定年。该提案的一个创新方面是将古地磁数据与赤铁矿测年相结合，为评估美国西部两项试点研究中的氧化铁数据和潜在的“双日期”流体流动事件提供背景。准确的解释和理解的意义的赤铁矿（U-Th）/He日期是必要的，然后才应用该技术的其他设置，如Baffin Island.How和为什么的火山区，或长期被认为是免疫构造作用的大陆的核心，被重新激活和签名的火山表面演化的这些过程仍然是大陆动力学中悬而未决的问题。这项研究的结果将是感兴趣的地质年代学和构造社区。重建过去的范围和厚度的沉积岩沉积在整个Rae克拉通和埋藏温度的量化将有助于冰川学家和地貌学家探索劳伦泰德冰盖动态的影响巴芬岛景观，但也将提供关键信息，了解区域油气藏的潜力在加拿大北极地区。赤铁矿（U-Th）/He定年技术的发展和成功应用，将使活动构造和经济地质学界受益。与这项研究相关的教育活动包括指导亚利桑那大学的本科生和研究生，并共同教授一个关于新的赤铁矿（U-Th）/He测年技术的方法和应用的暑期学生研讨会。

Dr. Alexis K. Ault has been granted an NSF Earth Sciences Postdoctoral Fellowship to carry out research and an education plan at the University of Arizona. This research investigates the surface response of cratons to near-field plate boundary activity including deformation, sedimentation from regions of high topography, foreland basin development, flexural uplift, and exhumation-related fluid-circulation. The proposed research focuses on the Rae craton, exposed on Baffin Island, Canada, a unique cratonic locality given its proximity to plate boundaries throughout the Phanerozoic, and aims to constrain the magnitudes and patterns of cratonic burial and unroofing with a suite of thermochronometers including apatite (U-Th)/He, apatite fission-track, and zircon (U-Th)/He dating. Fluid flow and secondary mineralization associated with rock exhumation, will be dated via hematite (U-Th)/He dating. An innovative aspect of this proposal is the coupling of paleomagnetic data with the hematite dating to provide a backdrop to evaluate Fe-oxide data and potentially "double-date" fluid flow events in two Western U.S. pilot studies. Accurate interpretation and understanding of the significance of hematite (U-Th)/He dates is necessary before application of the technique to other settings like Baffin Island.How and why cratonic regions, or the cores of continents long considered to be immune to tectonism, are reactivated and the signatures of such processes on the surface evolution of cratons remain outstanding questions in continental dynamics. The results of this research will be of interest to the geochronology and tectonics communities. Reconstruction of the past extent and thickness of sedimentary rocks deposited across the Rae craton and quantification of burial temperatures will aid glaciologists and geomorphologists exploring the impact of Laurentide ice sheet dynamics on the Baffin Island landscape, but will also provide critical information for understanding regional hydrocarbon reservoir potential in the Canadian Arctic. The development and successful application of the hematite (U-Th)/He dating technique to constrain near-surface fluid flow will benefit those in the active tectonics and economic geology communities. Education activities associated with this research include mentoring University of Arizona undergraduate and graduate students and co-teaching an intensive summer student workshop on the method and application of the new hematite (U-Th)/He dating technique.