Collaborative Research: Reconstructing paleo-sediment flux from river deposits: toward quantifying sediment discharge from bedform to basin scale

限制古代河流携带的泥沙数量为了解地球历史上的景观状况提供了一个窗口。它还有助于预测沉积盆地中油气、水、矿物和地热资源的埋藏位置。该项目旨在促进我们对泥沙如何通过河床、堤坝和堤坝转移的理解，以帮助i)回答有关河流对构造、气候和海平面变化的响应的问题，ii)了解地球和其他星球上河流运动的控制，以及iii)预测地下能源开发、矿产勘探和含水层管理的最佳地点。该项目正在为任职人数不足的群体的学生提供培训机会，从而帮助培养一支多样化的地球科学队伍。这项研究还产生了大型数据集--可通过数据仓库获得--实验平台特征和按比例进行的地层测量，这将是一种宝贵的教学资源，对地质学家、地貌学家和土木工程师都很有用。此外，研究人员正在开发迷你教程和虚拟野外旅行，可以作为学生的课堂练习，也可以作为科学家的露头解释练习，包括那些获得野外经验有限的科学家。正在将图像和图像解释纳入机器学习项目，以支持开发露头自动解释工具。该项目正在利用地貌学和沉积地质学的进展，将沉积物供应在多个尺度上的沉积物输送过程中的作用与地层产品定量地联系起来。物理实验、模拟和现场观测相结合的方法被用来细化对河床、沙洲和河道的泥沙输运速率的物理约束，并量化这些特征在地层记录中的形状和保存如何与不同尺度上的泥沙通量条件有关。这一见解正被应用于西班牙比利牛斯山脉的沉积物--一个具有强大的盆地尺度沉积物通量约束的系统--作为一项实地校准工作。随后，所开发的方法可以帮助定量检验关于古新世-始新世最热气候变化事件所发生的沉积物供应变化的假说。这些努力为沉积物在河流景观中如何在不同但相互关联的地貌动力学过程之间进行分配提供了新的见解，并提供了环境和土地利用变化如何影响百年到千年时间尺度上的河流流动性的指南。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。

Constraining the quantity of sediment carried by ancient rivers provides a window into landscape conditions throughout Earth’s history. It also facilitates the prediction of where hydrocarbon, water, mineral, and geothermal resources are buried in sedimentary basins. This project aims to advance our understanding of how sediment is transferred through the beds, bars, and levees of rivers in order to help i) answer questions about river response to changes in tectonics, climate, and sea level, ii) understand controls on river movements on Earth and other planets, and iii) predict the best places for underground energy development, mineral exploration and aquifer management. This project is providing training opportunities for students from underrepresented groups, thereby helping to develop a diverse geoscience workforce. This research is also producing large datasets—made available via data repositories— of experimental bedform characteristics and scaled stratigraphic measurements that will be a valuable teaching resource, and useful for geologists, geomorphologists, and civil engineers alike. In addition, the researchers are developing mini-tutorials and virtual field trips that can be used as classroom exercises for students and outcrop-interpretation exercises for scientists, including those with limited access to field experiences. Images and image interpretations are being incorporated into the machine learning project to support the development of automated outcrop interpretation tools. This project is leveraging advances in geomorphology and sedimentary geology to quantitatively connect the role of sediment supply in sediment-transport processes across multiple scales to stratigraphic products. A combination of physical experiments, modeling, and field observations is being used to refine physical constraints on sediment transport rates of bedforms, bars, and channels, and to quantify how the shape and preservation of these features in the stratigraphic record relate to sediment-flux conditions at different scales. This insight is being applied to deposits of the Spanish Pyrenees – a system with robust basin-scale sediment-flux constraints – as a field calibration exercise. Subsequently, the developed approaches can help quantitatively test hypotheses about sediment-supply changes that occurred in response to the Paleocene-Eocene Thermal Maximum climate-change event. These efforts are yielding new insight into how sediment is partitioned between distinct but interrelated morphodynamic processes in fluvial landscapes, and providing a guide to how environmental and land-use change can affect river mobility on centennial to millennial timescales.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.