Shortening, extension, and drainage reorganization in the Andean fold-thrust belt and broken foreland basin of northern Patagonia, Argentina

阿根廷巴塔哥尼亚北部安第斯褶皱冲断带和破碎前陆盆地的缩短、延伸和排水重组

• 批准号: 1918541
• 负责人: Brian Horton
• 金额: $ 44.03万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1918541&HistoricalAwards=false
• 关键词: Shortening; extension; drainage; reorganization; Andean

The Andes Mountains of South America are a key location for mountain building along convergent plate tectonic boundaries where an overriding continental plate is deformed above a subducting oceanic plate. Although Andean mountain building is generally associated with regional collision and shortening of continental crust, recent studies point to important examples of extensional deformation. This research project will address the long-term history of crustal deformation in the northern Patagonian Andes, where alternations between shortening and extension appear to have influenced the generation of topography, erosion, river drainage systems, and sedimentary basins. The project will utilize a variety of analytical techniques, including sedimentary basin analysis, geochronology, and structural geology to determine the age, duration, and depositional processes within the Patagonian basin of southern Argentina. The project will help define processes within the Earth's crust and at the surface that influence the formation of sedimentary basins produced by both shortening and extensional deformation. The study will have implications for understanding the fundamental geologic processes and associated geohazards along ocean-continent plate boundaries, offering societal benefits in the form of information that will enable improved risk assessment and infrastructure planning. In addition, the project will initiate international scientific collaborations between academic and industry scientists and support international research and training opportunities for undergraduate and graduate students.The project will address an emerging debate for the Andes regarding the role of extension during what has been long regarded as uninterrupted shortening, thickening, and uplift along an extensive subduction margin. An orogenic system that fluctuates between compressional and extensional stresses may govern the structural and stratigraphic evolution of Andean-type convergent systems, due to both margin-wide changes in mechanical coupling driven by plate kinematics (rollback/retreating vs. advancing margin) and more-regional changes in subducting-slab dynamics (slab shallowing vs. steepening). This project will focus on an understudied segment of the Andean fold-thrust belt and broken foreland region of northern Patagonia, which contains evidence of not only Cretaceous-Cenozoic shortening and foreland basin evolution but also extensional basin development and drainage reorganization during irregular advance and retreat of the Andean magmatic arc. The research team will conduct a sedimentary/structural basin analysis and restoration of a regional east-west transect in southern Argentina, that will include an enhanced depositional and deformational record, dating of basin-bounding structures, new U-Pb chronostratigraphic and provenance constraints, and revised subsidence and magmatic histories. The results will enable integration across several basin systems in order to identify the patterns of basin genesis, unconformity development, sediment routing, and drainage reorganization during contrasting phases of shortening, extension, and stasis in the southern Andes.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.

南美洲的安第斯山脉是沿着会聚板块构造边界造山的关键地点，其中压倒性的大陆板块在俯冲的海洋板块上方变形。 尽管安第斯山脉的形成通常与区域碰撞和大陆地壳缩短有关，但最近的研究指出了伸展变形的重要例子。 该研究项目将研究巴塔哥尼亚安第斯山脉北部地壳变形的长期历史，那里的缩短和伸展之间的交替似乎影响了地形、侵蚀、河流排水系统和沉积盆地的形成。 该项目将利用各种分析技术，包括沉积盆地分析、地质年代学和构造地质学，以确定阿根廷南部巴塔哥尼亚盆地的年龄、持续时间和沉积过程。该项目将帮助定义地壳内部和地表的过程，这些过程影响由缩短和伸展变形产生的沉积盆地的形成。该研究将对了解沿洋大陆板块边界的基本地质过程和相关地质灾害产生影响，以信息的形式提供社会效益，从而改进风险评估和基础设施规划。 此外，该项目还将启动学术界和工业界科学家之间的国际科学合作，并为本科生和研究生提供国际研究和培训机会。该项目将解决安第斯山脉正在出现的一场争论，即安第斯山脉在长期以来被认为沿着广泛的俯冲边缘不间断缩短、增厚和隆起过程中的伸展作用。 由于板块运动学驱动的机械耦合的边缘范围变化（回滚/后退与前进边缘）以及俯冲板片动力学的更多区域变化（板片变浅与陡峭），在压缩应力和拉伸应力之间波动的造山系统可能控制安第斯型会聚系统的结构和地层演化。 该项目将重点研究安第斯褶皱逆冲带和巴塔哥尼亚北部破碎前陆地区的待研究部分，其中不仅包含白垩纪-新生代缩短和前陆盆地演化的证据，而且还包含安第斯岩浆弧不规则进退过程中伸展盆地发育和流域重组的证据。 研究小组将对阿根廷南部的区域东西向横断面进行沉积/构造盆地分析和恢复，其中包括增强的沉积和变形记录、盆地边界结构的测年、新的 U-Pb 年代地层和物源限制，以及修正的沉降和岩浆历史。 研究结果将实现跨多个盆地系统的整合，以确定安第斯山脉南部缩短、延伸和停滞的对比阶段的盆地成因、不整合面发育、沉积物演进和排水重组的模式。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。

项目成果

Unconformity development in retroarc foreland basins: implications for the geodynamics of Andean-type margins

• DOI: 10.1144/jgs2020-263
• 发表时间: 2021-12-01
• 期刊: JOURNAL OF THE GEOLOGICAL SOCIETY
• 影响因子: 2.7
• 作者: Horton, Brian K.

The origin of the San Jorge Gulf Basin in the context of the Mesozoic-Cenozoic evolution of Patagonia

• DOI: 10.1016/j.jsames.2019.102422
• 发表时间: 2020
• 期刊: Journal of South American Earth Sciences
• 影响因子: 1.8
• 作者: A. Folguera;L. F. Paz;S. Iannelli;C. Navarrete;A. Echaurren;G. Gianni;K. Butler;B. Horton

Cretaceous-Cenozoic growth of the Patagonian broken foreland basin, Argentina: Chronostratigraphic framework and provenance variations during transitions in Andean subduction dynamics

阿根廷巴塔哥尼亚破碎前陆盆地的白垩纪-新生代生长：安第斯俯冲动力学过渡期间的年代地层框架和物源变化

• DOI: 10.1016/j.jsames.2019.102242
• 发表时间: 2020
• 期刊: Journal of South American Earth Sciences
• 影响因子: 1.8
• 作者: Butler, Kristina L.;Horton, Brian K.;Echaurren, Andrés;Folguera, Andrés;Fuentes, Facundo
• 通讯作者: Fuentes, Facundo

Neogene Retroarc Foreland Basin Evolution, Sediment Provenance, and Magmatism in Response to Flat Slab Subduction, Western Argentina

• DOI: 10.1029/2019tc005958
• 发表时间: 2020-07-01
• 期刊: TECTONICS
• 影响因子: 4.2
• 作者: Capaldi, Tomas N.;Horton, Brian K.;Alvarado, Patricia
• 通讯作者: Alvarado, Patricia

Andean Mountain Building and Foreland Basin Evolution During Thin‐ and Thick‐Skinned Neogene Deformation (32–33°S)

新近纪薄皮和厚皮变形期间的安第斯山脉建造和前陆盆地演化（南纬32°至33°）

• DOI: 10.1029/2019tc005838
• 发表时间: 2020
• 期刊: Tectonics
• 影响因子: 4.2
• 作者: Mackaman‐Lofland, Chelsea;Horton, Brian K.;Fuentes, Facundo;Constenius, Kurt N.;Ketcham, Richard A.;Capaldi, Tomas N.;Stockli, Daniel F.;Ammirati, Jean‐Baptiste;Alvarado, Patricia;Orozco, Paola
• 通讯作者: Orozco, Paola