RUI: Collaborative Research: Early Cenozoic basin development in the southwestern US: a record of extensional collapse following subduction of an oceanic plateau?

RUI：合作研究：美国西南部新生代早期盆地发育：海洋高原俯冲后伸展塌陷的记录？

• 批准号: 1946349
• 负责人: Francis Sousa
• 金额: $ 12.01万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-01 至 2024-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1946349&HistoricalAwards=false
• 关键词: RUI; Collaborative; Research; Early; Cenozoic

Subduction zones represent some of the most tectonically active regions on earth. Changes in the angle of the downgoing plate can control volcanism, faulting, and basin development in the overlying continental crust. The Maniobra and Goler Formations, exposed in the Mojave Desert in southern California, provide evidence for the development of extensional basins on the overriding continental plate related to low-angle subduction in Late Cretaceous to Eocene time (~80-50 million years ago). This research will test the hypothesis that Late Cretaceous extension resulted in the development of the Maniobra and Goler Basins, while simultaneously introducing more than 50 undergraduate and 2 Masters students to the techniques of basin analysis. The field sites in the Mojave Desert, located within 3 hours of Los Angeles, provide a natural laboratory to train the next generation of geoscientists. Students from a Hispanic-serving institution will learn modern geologic techniques, such as geologic mapping, geochronology, paleomagnetism, and thermochronology, that can be applied to their graduate and post-graduate careers. Analytical data from this research will be made available on community databases, and results of the proposed research will be used to construct a publicly-available online learning module.Recent tectonic models of the southwestern US Cordillera have invoked the subduction of an oceanic plateau, the conjugate Shatsky Rise, as a driver of slab flattening, subduction erosion and arc cessation in Late Cretaceous to Eocene time. Subduction, and subsequent passage of the plateau, likely promoted extension and associated regional paleogeographic changes, such as basin development and block rotations. This study targets the Goler and Maniobra Formations, which are the only Late Cretaceous to Eocene basinal strata located along the interpreted subduction pathway. This research will test the hypothesis that gravitational collapse in the wake of plateau subduction was widespread across the Mojave region in the Late Cretaceous to early Cenozoic and led to the development of supra-detachment basins and the exhumation of relict subduction complexes. This research will incorporate new mapping of stratigraphic and structural relationships, combined with magnetostratigraphy, detrital zircon provenance analysis, and basement and detrital thermochronology. This data will constrain the timing and duration of basin formation and enable the evaluation of different tectonic models of basin development. New basin analysis results from the Late Cretaceous to Eocene Goler and Maniobra Formations will provide a crucial link between plateau subduction processes and related surface deformation and will highlight the complexity of tectonic evolution along a highly segmented margin over time.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.

俯冲带代表地球上一些最具构造活性的区域。下层板的角度的变化可以控制上覆的大陆壳中的火山，断层和盆地发育。在南加州的莫哈韦沙漠中暴露的Maniobra和Goler地层为在白垩纪晚期到始新世时代晚期（约80-50万年前）的低角度俯冲相关的大陆板上开发了延伸盆地的证据。这项研究将检验以下假设：晚白垩纪延伸导致了Maniobra和Goler盆地的发展，同时同时将50多个本科生和2名硕士生引入了盆地分析技术。位于洛杉矶3小时内的莫哈韦沙漠中的田野提供了一个自然实验室，以训练下一代地球科学家。来自西班牙裔服务机构的学生将学习现代地质技术，例如地质制图，地质学，古磁学和热量学，可以应用于其研究生和研究生职业。 Analytical data from this research will be made available on community databases, and results of the proposed research will be used to construct a publicly-available online learning module.Recent tectonic models of the southwestern US Cordillera have invoked the subduction of an oceanic plateau, the conjugate Shatsky Rise, as a driver of slab flattening, subduction erosion and arc cessation in Late Cretaceous to Eocene time.俯冲以及高原的随后通过，可能会促进扩展和相关的区域古地理变化，例如盆地发展和阻塞旋转。这项研究针对的是Goler和Maniobra地层，这是沿解释的俯冲途径唯一的白垩纪晚期始新世盆地地层。这项研究将检验以下假设：在高原俯冲之后的引力崩溃在晚白垩纪到早期的莫哈韦地区广泛存在，并导致了远景盆地的发展，并挖掘出了遗物俯冲复合物。这项研究将结合地层和结构关系的新映射，并结合磁层学，碎屑锆石出处分析以及地下室和碎屑热体学。该数据将限制盆地形成的时间和持续时间，并能够评估盆地发展的不同构造模型。新的盆地分析结果来自白垩纪晚期到始新世的gol和Maniobra的形态将在高原俯冲过程和相关的表面变形之间提供至关重要的联系，并将强调沿时间沿高度分段边缘的复杂性，随着时间的推移，这是NSF的法定任务，反映出值得评估的构成者，这一奖项被认为是构成的范围。