CAREER: Integrating research and education to evaluate Neoproterozoic-Cambrian tectonism and sedimentary basins in western Laurentia

该项目旨在提高对罗迪纳新元古代超大陆分裂的时间和性质的理解，这是一个有争议的话题，对海洋化学和生命的同时代变化具有重要影响。该项目的成果将包括北美西部多个地区的综合地层学、地质年代学和地球化学数据集。这些原始数据集将依次用于为每个区域生成新的沉降曲线。结合起来，这些产品可用于区分劳伦古大陆西缘新元古代-寒武纪裂谷的不同模型。该协同教育计划将侧重于通过分层指导系统、开发包容性实地课程和实地论坛，改善研究和课程作业中户外实地工作的机会。该项目的更广泛影响将侧重于通过与巴尔的摩独创项目（Baltimore Ingenuity Project）合作，为巴尔的摩市内服务不足的人群提供支持，并扩大对地球科学的参与。巴尔的摩独创性项目是当地的一个非营利组织，从历史上服务不足的人群中招募和培养对 STEM 具有高潜力和兴趣的中学生和高中生。罗迪尼亚新元古代超大陆分裂的时间和性质仍然存在争议，古地理重建与罗迪尼亚核心古大陆劳伦西亚西缘保存的地质记录之间存在重大不一致。评估对劳伦大陆边缘构造历史的这些不同解释，需要对劳伦大陆西部新元古代-寒武纪盆地沉降、裂谷相关构造活动和火山活动的构造地层背景和年龄模型进行重大改进，这需要新的地质年代学约束和更好地校准这些沉积盆地内的不整合面。该提案的研究目标是通过战略性地关注位于美国西部、墨西哥北部和不列颠哥伦比亚省的特定新元古代-寒武纪沉积盆地的地质历史来区分西劳伦西亚提出的不同构造模型。选择这些区域是因为它们沿边缘的关键地理位置，以及这些序列中已识别和描述的双峰火山岩。该项目的目标将通过整合地质测绘、区域地层学、页岩地球化学、U-Pb地质年代学和沉降模型来实现，以解决有关西劳伦大陆裂谷动力学的一些长期争论，并改进新元古代晚期超大陆分裂的时间和地理模型。拟议的科学研究议程与拟议的教育和指导计划具有协同作用，重点是通过以下方式改善户外实地工作的机会：1）分层指导系统，2）包容性实地课程的开发和教学，3）死亡谷实地论坛，以及4）综合研究、指导和更广泛的影响。该项目将支持巩固北美西部构造运动、沉积盆地发育和地球生命变化的综合研究和实地教育事业的基础。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to improve understanding of the timing and nature of the breakup of the Neoproterozoic supercontinent of Rodina, a contentious topic that has important implications for coeval changes in ocean chemistry and life. The results of this project will include integrated stratigraphic, geochronological, and geochemical datasets from several regions in western North America. These original datasets will, in turn, be used to generate new subsidence curves for each of these areas. Combined, these products can be used to discriminate between different models that have been proposed for Neoproterozoic–Cambrian rifting on the western margin of the paleocontinent of Laurentia. The synergistic educational plan will focus on improving access to Outdoor Field Work in research and coursework through a tiered mentoring system, development of inclusive field-based courses, and a field forum. The Broader Impacts of this project will focus on empowering underserved populations and broadening participation in the geosciences within Baltimore City through collaboration with the Baltimore Ingenuity Project, a local non-profit which recruits and cultivates middle and high school students with high potential and interest in STEM and from historically underserved populations. The timing and nature of the breakup of the Neoproterozoic supercontinent of Rodinia has remained contentious, with major inconsistencies existing between paleogeographic reconstructions and the geologic records preserved along the western margin of Laurentia, the paleocontinent at the core of Rodinia. Evaluating these divergent interpretations for the tectonic histories of Laurentia’s margins requires significant improvements to the tectonostratigraphic context and age models for Neoproterozoic–Cambrian basin subsidence, rift-related tectonism, and volcanism in western Laurentia, which demand new geochronological constraints and better calibration of unconformities within these sedimentary basins. The research goal of this proposal is to discriminate between different proposed tectonic models for western Laurentia by strategically focusing on the geologic histories of specific Neoproterozoic–Cambrian sedimentary basins located in the western USA, northern Mexico, and British Columbia. These regions are chosen because of their key geographic locations along the margin and because of identified and described bimodal volcanic rocks in these successions. The goals of this project will be achieved by integrating geologic mapping, regional stratigraphy, shale geochemistry, U–Pb geochronology, and subsidence modeling to resolve some of the long-standing debates about rift dynamics in western Laurentia and to improve temporal and geographic models for late Neoproterozoic supercontinent breakup. The proposed scientific research agenda is synergistic with the proposed educational and mentorship plans, which focus on improving access to Outdoor Field Work through: 1) a tiered mentoring system, 2) development and teaching of inclusive field-based courses, 3) a Death Valley Field Forum, and 4) integrated research, mentoring, and Broader Impacts. The project will support cementing a foundation for a career of integrated research and field-based education on studying tectonism, sedimentary basin development, and Earth-life changes in western North America.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.