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得到证实，但它是地球上最后一个现代海洋盆地，其起源仍然存在很大争议。这主要是由于其常年冰盖和缺乏船载研究船进行详细的科学检查。拟议研究的目标是检查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，该断层系统可能在北冰洋的开放过程中发挥了重要作用，但人们对此知之甚少。该研究促进了美国四家机构以及美国和加拿大政府研究机构的早期职业研究人员和高级学术研究人员之间的新合作，包括开发跨越国际边界的新地质测绘工作。这项国际合作努力将与美国鱼类和野生动物管理局以及内华达州拉斯维加斯合作，通过与 NSF 支持的 GeoPaths 计划相结合，为学术机构的本科生和研究生提供研究机会和培训，并为阿拉斯加原住民社区提供教育和推广机会。该项目的结果还将通过由阿拉斯加美国鱼类和野生动物管理局赞助和分发的信息小册子以及在参与大学举办的公开讲座向公众传达。北冰洋加拿大盆地开口的典型构造模型涉及侏罗纪-白垩纪阿拉斯加北部远离加拿大北极群岛的逆时针旋转超过60°，但最近的模型强调了潜在的重要意义沿北美北缘的走滑位移。至关重要的是，我们对可能适应这些边缘平行位移的断层系统知之甚少。这项研究的目的是研究豪猪断层系统，这是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结构，人们对它的中生代-新生代再活动历史知之甚少，但很可能在加拿大盆地的开放过程中发挥了作用。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，这不仅将进一步加深我们对环北极、北太平洋和北美科迪勒拉山脉北部中生代构造和古地理模型的理解，而且还将为多相脆性断层系统中地壳变形的动力学和年代学提供新的见解。此外，该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与这些复杂系统相结合的实用性和可行性。因此，该项目将引起构造学、构造地质学和地质/热年代学界的广泛兴趣，以及北极科学、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价值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.