Collaborative Research: The Role of the Porcupine Fault System in the Mesozoic Opening of the Arctic Ocean

尽管北冰洋的经济资源已被证实，但它是地球上最后一个起源仍存在极大争议的现代洋盆。这在很大程度上是由于其常年的冰盖和缺乏舰载考察船的详细科学检查。这项拟议中的研究的目标是研究阿拉斯加东北部和加拿大育空地区西北部的豪猪断层系统，该系统可能在北冰洋的开放中发挥了重要但鲜为人知的作用。这项研究促进了美国和加拿大四个美国机构和政府研究机构的早期职业和高级学术研究人员之间的新合作，包括开发一项跨越国际边界的新地质制图工作。合作的国际努力将为学术机构的本科生和研究生创造研究机会和培训，并通过与美国鱼类和野生动物服务中心和内华达州拉斯维加斯的合作，通过与NSF支持的GeoPath计划的整合，在阿拉斯加的农村原住民社区创造教育和推广机会。该项目的成果还将通过在阿拉斯加由美国鱼类和野生动物服务局赞助和分发的信息小册子的开发以及参与大学的公开讲座向公众传达。北冰洋加拿大盆地开放的典型构造模型包括阿拉斯加北部在侏罗纪-白垩纪逆时针旋转超过60°，远离加拿大北极群岛，但最近的模型强调了北美北部边缘潜在的显著走滑位移。关键的是，人们对可能容纳了这些边缘平行位移的断层系统知之甚少。这项拟议研究的目标是研究豪猪断层系统，这是位于阿拉斯加东北部和加拿大育空地区西北部的一个长期存在的克拉通边界构造，它的中新生代重新激活历史鲜为人知，但可能在加拿大盆地的开放中发挥了作用。这反映了早期职业和高级学术研究人员、联邦和州/地区地球科学家以及本科生/研究生之间的新合作，这不仅将加深我们对环北极、北太平洋和北美科迪勒拉地区中新生代构造和古地理模型的理解，而且还将为多期脆性断裂系统中地壳变形的动力学和年代学提供新的见解。此外，研究还将测试将多个已建立的和新的断层地质和温度计时仪组合在这些复杂系统中的实用性和可行性。因此，这个项目将引起构造学、构造地质学和地球/热年代学领域的广泛兴趣，以及对北极科学、经济地质学、沉积地质学、岩石学、地球物理学和地球动力学的跨学科兴趣。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Despite its proven economic resources, the Arctic Ocean is the last modern ocean basin on the planet whose origin remains highly controversial. This is largely due to its perennial ice cover and lack of detailed scientific examination by shipborne research vessels. The goal of the proposed research is to examine the Porcupine fault system in northeastern Alaska and northwestern Yukon, Canada, which likely played an important, yet poorly understood, role in the opening of the Arctic Ocean. The study promotes a new collaboration between early career and senior academic researchers at four U.S. institutions and government research agencies in both the United States and Canada, including the development of a new geologic mapping effort across the international border. The collaborative international effort will generate research opportunities and training for undergraduate and graduate students at the academic institutions, as well as educational and outreach opportunities in a rural Native Alaskan community in collaboration with the United States Fish and Wildlife Service and Las Vegas, NV, through integration with the NSF-supported GeoPaths program. Results of the project will also be conveyed to the public through the development of an informational pamphlet sponsored and distributed by the U.S. Fish and Wildlife Service in Alaska, as well as accessible public lectures at the participating universities.The canonical tectonic model for the opening of the Canada Basin of the Arctic Ocean involves greater than 60º counterclockwise rotation of northern Alaska away from the Canadian Arctic Islands in the Jurassic–Cretaceous, but more recent models highlight potentially significant strike-slip displacement along the northern margin of North America. Critically, little is known about the fault systems that may have accommodated these margin-parallel displacements. The goal of the proposed research is to examine the Porcupine fault system, a long-lived craton-bounding structure in northeastern Alaska and northwestern Yukon, Canada, that has a poorly understood Mesozoic–Cenozoic reactivation history but likely played a role in the opening of the Canada Basin. The reflects a new collaboration between Early Career and senior academic researchers, federal and state/territory geoscientists, and undergraduate/graduate students that will not only further our understanding of Mesozoic–Cenozoic tectonic and paleogeographic models for the circum-Arctic, northern Pacific, and northern North American Cordillera, but it will also provide new insights into the dynamics and chronology of crustal deformation in polyphase brittle fault systems. In addition, the research will test the utility and feasibility of combining multiple established and new fault geo- and thermo-chronometers to these complex systems. As a result, this project will generate broad interest from the tectonics, structural geology, and geo-/thermo-chronology communities, as well as cross-disciplinary interest in Arctic sciences, economic geology, sedimentary geology, petrology, geophysics, and geodynamics.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.