Collaborative Research: Processes Driving Rock Uplift and Flexural Deformation following Convergent Tectonics: The Fluvial Terrace Record, Ebro Basin, Spain

合作研究：聚合构造后驱动岩石隆起和弯曲变形的过程：西班牙埃布罗盆地河流台地记录

• 批准号: 0088601
• 负责人: Eric McDonald
• 金额: $ 15万
• 依托单位: Nevada System of Higher Education, Desert Research Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0088601&HistoricalAwards=false
• 关键词: Collaborative; Research; Processes; Driving; Rock

Lewis 0088714McDonald 0088601Establishing dynamic links between rock uplift and long-term patterns and rates of fluvial incision away from plate margins is a major contemporary challenge in tectonic geomorphology. We are engaged in a multifaceted project that addresses fundamental questions about how mountainous topography and fluvial systems evolve following active crustal shortening. The Spanish Pyrenees and adjacent Ebro Basin comprise an outstanding locality for isolating processes that drive rock-uplift (or subsidence) in orogens where active compression and crustal thickening have ceased. A marked feature of the Ebro Basin is the striking variation in stream incision into ~25 million year old sedimentary rocks. Incision is minimal along the axis of the basin, but reaches more than 1000 m in the south-central Pyrenees. Our data suggest that long-term patterns and rates of fluvial incision in ranges flanking the Ebro Basin are driven by intraplate phenomena, which form the three competing hypotheses we are testing: Streams in this region incise in response to one, or more, of the following mechanisms: (1) rock uplift by isostatic response to removal of mass from the orogen and adjacent foreland basin; (2) rock uplift driven by upwelling of hot, buoyant asthenosphere perhaps related to adjacent, active crustal extension and volcanism; (3) regional base level lowering, perhaps related to the Messinian salinity crisis, Quaternary eustatic sea level changes, or both. We are developing a precise chronostratigraphy (based on radiocarbon, luminescence, and cosmogenic nuclide dating and soils) of selected stream terraces in the Ebro Basin for which spatial and temporal rates of fluvial incision can be reconstructed. Results will be used to generate a conceptual model for the processes that drive rock-uplift (or subsidence) in orogens where active crustal thickening has ceased. Our multidisciplinary approach requires expertise in structural geology, soil stratigraphy, geochronology, tectonic geomorphology, geodynamic modeling, and regional geology. We focus on the central Pyrenees for this work, but our methodology has direct application to both modern and ancient mountain ranges throughout the world.

路易斯0088714MCDONALD 0088601建立岩石隆起与长期模式之间的动态联系，而河流切口的速率是构成地貌的主要当代挑战。 我们参与了一个多面项目，该项目解决了有关在主动地壳缩短后如何发展山地形状和河流系统的基本问题。 西班牙比利牛斯山脉和邻近的埃布罗盆地包括一个出色的地方，用于隔离过程，该过程驱动岩石（或沉降）在有效的压缩和地壳增厚的Orogens中驱动岩石（或沉降）。 EBRO盆地的一个明显特征是溪流切口的惊人变化到约2500万年历史的沉积岩。 切口沿着盆地的轴最小，但在中南部的比利牛斯山脉中达到1000 m以上。 我们的数据表明，EBRO盆地侧面范围内的河流切口的长期模式和速率是由板岩内现象驱动的，构成了我们正在测试的三个竞争假设：该区域中的三个相互竞争的假设：响应于一个或更多的机制，以下机制：（1）（1）因质量响应的质量响应质量的质量，而质量依次依次，而相互响应的质量依次依次，则相互响应。 （2）由热，浮动性的软圈上升驱动的岩石提升，可能与相邻的，活跃的地壳延伸和火山相关； （3）降低区域基础水平，可能与梅西尼亚盐度危机，第四纪厄斯特海平面变化或两者有关。 我们正在EBRO盆地中选定的溪流露台上开发一个精确的年度地层学（基于放射性碳，发光和宇宙核素约会和土壤），可以重建河流切口的空间和时间速率。 结果将用于生成一个概念模型，以驱动驱动岩石（或沉降）的过程中，在活跃的地壳增厚的牛根中驱动岩石（或沉降）。 我们的多学科方法需要结构地质，土壤地层学，地质学，构造地貌，地球动力学建模和区域地质学方面的专业知识。 我们专注于这项工作的中央比利牛斯山脉，但是我们的方法论直接应用于世界各地的现代和古老山脉。